#!@TERMUX_PREFIX@/bin/bash
# shellcheck disable=SC2239
##
## Proot-Distro is a script for managing proot containers on Termux.
##
## !!!        THIS IS NOT A REPLACEMENT FOR PROOT UTILITY        !!!
##
## Originally created by Sylirre <sylirre@termux.dev> for Termux project.
##
## This program is free software: you can redistribute it and/or modify
## it under the terms of the GNU General Public License as published by
## the Free Software Foundation, either version 3 of the License, or
## (at your option) any later version.
##
## This program is distributed in the hope that it will be useful,
## but WITHOUT ANY WARRANTY; without even the implied warranty of
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
## GNU General Public License for more details.
##
## You should have received a copy of the GNU General Public License
## along with this program. If not, see <http://www.gnu.org/licenses/>.
##

PROGRAM_VERSION="4.34.2"

#############################################################################
#
# GLOBAL ENVIRONMENT AND INSTALLATION-SPECIFIC CONFIGURATION
#

set -e -u

# Keep LD_PRELOAD value for restoring after unset.
TERMUX_LDPRELOAD="${LD_PRELOAD-}"

# Override user-defined PATH.
export PATH="@TERMUX_PREFIX@/bin"

# Reference this where need to retrieve program name.
PROGRAM_NAME=$(basename "$(realpath "$0")")

# Where distribution plug-ins are stored.
DISTRO_PLUGINS_DIR="@TERMUX_PREFIX@/etc/proot-distro"

# Base directory where script keeps runtime data.
RUNTIME_DIR="@TERMUX_PREFIX@/var/lib/proot-distro"

# Where rootfs archives are downloaded.
DOWNLOAD_CACHE_DIR="${RUNTIME_DIR}/dlcache"

# Where extracted rootfs are stored.
INSTALLED_ROOTFS_DIR="${RUNTIME_DIR}/installed-rootfs"

# Default name servers.
DEFAULT_PRIMARY_NAMESERVER="8.8.8.8"
DEFAULT_SECONDARY_NAMESERVER="8.8.4.4"

# PATH environment variable for distributions.
DEFAULT_PATH_ENV="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/local/games:/usr/games:@TERMUX_PREFIX@/bin:/system/bin:/system/xbin"

# Default fake kernel version.
# Note: faking kernel version is required when using PRoot-Distro on
# old devices that are not compatible with up-to-date versions of GNU libc.
DEFAULT_FAKE_KERNEL_RELEASE="6.17.0-PRoot-Distro"
DEFAULT_FAKE_KERNEL_VERSION="#1 SMP PREEMPT_DYNAMIC Fri, 10 Oct 2025 00:00:00 +0000"

# Emulator type for x86_64 systems.
# Can be either BLINK or QEMU.
: "${PROOT_DISTRO_X64_EMULATOR:=QEMU}"

# Colors.
if [ -n "$(command -v tput)" ] && [ "$(tput colors 2>/dev/null || echo 0)" -ge 8 ] && [ -z "${PROOT_DISTRO_FORCE_NO_COLORS-}" ]; then
	RST="$(tput sgr0)"
	RED="${RST}$(tput setaf 1)"
	BRED="${RST}$(tput bold)$(tput setaf 1)"
	GREEN="${RST}$(tput setaf 2)"
	YELLOW="${RST}$(tput setaf 3)"
	BYELLOW="${RST}$(tput bold)$(tput setaf 3)"
	IYELLOW="${RST}$(tput sitm)$(tput setaf 3)"
	BLUE="${RST}$(tput setaf 4)"
	MAGENTA="${RST}$(tput setaf 5)"
	CYAN="${RST}$(tput setaf 6)"
	BCYAN="${RST}$(tput bold)$(tput setaf 6)"
	ICYAN="${RST}$(tput sitm)$(tput setaf 6)"
else
	RED=""
	BRED=""
	GREEN=""
	YELLOW=""
	BYELLOW=""
	IYELLOW=""
	BLUE=""
	MAGENTA=""
	CYAN=""
	BCYAN=""
	ICYAN=""
	RST=""
fi

# Override umask
umask 0022

#############################################################################
#
# FUNCTION TO PRINT A MESSAGE TO CONSOLE
#
# Prints a given text string to stderr. Supports escape sequences.
#
#############################################################################

msg() {
	echo -e "$@" >&2
}

#############################################################################
#
# DEPENDENCY CHECK
#
# Make sure all needed utilities are available in PATH before continuing.
#
#############################################################################

for i in awk basename bzip2 cat chmod cp curl cut du file find grep gzip \
	head id lscpu mkdir proot rm sed tar unzip xargs xz; do
	if [ -z "$(command -v "$i")" ]; then
		msg
		msg "${BRED}Utility '${i}' is not installed. Cannot continue.${RST}"
		msg
		exit 1
	fi
done
unset i

# Notify user if bin/bash is not a GNU Bash.
if ! grep -q '^GNU bash' <(bash --version 2>/dev/null | head -n 1); then
	msg
	msg "${BRED}Warning: bash binary that is available in PATH appears to be not a GNU bash. You may experience issues during installation, backup and restore operations.${RST}"
	msg
fi

# Notify user if tar available in PATH is not GNU tar.
if ! grep -q '^tar (GNU tar)' <(tar --version 2>/dev/null | head -n 1); then
	msg
	msg "${BRED}Warning: tar binary that is available in PATH appears to be not a GNU tar. You may experience issues during installation, backup and restore operations.${RST}"
	msg
fi

#############################################################################
#
# ANTI ROOT FUSE
#
# This script should never be executed as root as can mess up the ownership,
# and SELinux labels in $PREFIX.
#
#############################################################################

if [ "$(id -u)" = "0" ]; then
	msg
	msg "${BRED}Warning: ${PROGRAM_NAME} should not be executed as root user. Do not send bug reports about messed up Termux environment, lost data and bricked devices.${RST}"
	msg
fi

#############################################################################
#
# ANTI NESTED PROOT FUSE
#
# Nested PRoot usage leads to performance degradation and other issues.
#
#############################################################################

TRACER_PID=$(grep TracerPid "/proc/$$/status" | cut -d $'\t' -f 2)
if [ "$TRACER_PID" != 0 ]; then
	TRACER_NAME=$(grep Name "/proc/${TRACER_PID}/status" | cut -d $'\t' -f 2)
	if [ "$TRACER_NAME" = "proot" ]; then
		msg
		msg "${BRED}Error: ${PROGRAM_NAME} should not be executed under PRoot.${RST}"
		msg
		exit 1
	fi
	unset TRACER_NAME
fi
unset TRACER_PID

#############################################################################
#
# FUNCTION TO DETECT CPU ARCHITECTURE IN GIVEN DISTRIBUTION
#
# Check known executable(s) and return CPU architecture.
#
#############################################################################

detect_cpu_arch() {
	local dist_path="${INSTALLED_ROOTFS_DIR}/${1}"
	local cpu_arch

	local i
	for i in /bin/bash /bin/sh /bin/su /bin/busybox /data/data/com.termux/files/usr/bin/bash; do
		if [ "$(dd if="${dist_path}${i}" bs=1 skip=1 count=3 2>/dev/null)" = "ELF" ]; then
			cpu_arch=$(file -L "${dist_path}${i}" | cut -d':' -f2- | cut -d',' -f2 | cut -d' ' -f2-)
			[ -n "$cpu_arch" ] && break
		fi
	done

	case "$cpu_arch" in
		"ARM aarch64") cpu_arch="aarch64";;
		"ARM") cpu_arch="arm";;
		"UCB RISC-V") cpu_arch="riscv64";;
		"Intel 80386") cpu_arch="i686";;
		"x86-64") cpu_arch="x86_64";;
		*) cpu_arch="unknown";;
	esac

	echo "$cpu_arch"
}

#############################################################################
#
# FUNCTION TO INSTALL THE SPECIFIED DISTRIBUTION
#
# Brief algorithm how it works:
#
#  1. Process arguments supplied to 'install' command.
#  2. Ensure that requested distribution is supported and is not installed.
#  3. Source the distribution configuration plug-in.
#  4. Download the archive of rootfs for requested distribution unless found
#     in cache.
#  5. Verify SHA-256 checksum of the rootfs archive.
#  6. Extract the rootfs under PRoot with link2symlink extension enabled for
#     normal distributions and custom method for others.
#  7. Perform post-installation actions on distribution to make it ready.
#
#############################################################################

command_install() {
	local distro_name
	local override_alias
	local distro_plugin_script

	while (($# >= 1)); do
		case "$1" in
			--)
				shift 1
				break
				;;
			-h|--help)
				command_install_help
				return 0
				;;
			--override-alias)
				if [ $# -ge 2 ]; then
					shift 1

					if [ -z "$1" ]; then
						msg
						msg "${BRED}Error: argument to option '${YELLOW}--override-alias${BRED}' should not be empty.${RST}"
						command_install_help
						return 1
					fi

					if ! grep -qP '^[a-z0-9][a-z0-9_.+\-]*$' <<< "$1"; then
						msg
						msg "${BRED}Error: argument to option '${YELLOW}--override-alias${BRED}' should start only with an alphanumeric character and consist of alphanumeric characters including symbols '_.+-'."
						msg
						return 1
					fi

					if grep -qP '^.*\.sh$' <<< "$1"; then
						msg
						msg "${BRED}Error: argument to option '${YELLOW}--override-alias${BRED}' should not end with '.sh'.${RST}"
						msg
						return 1
					fi

					override_alias="$1"
				else
					msg
					msg "${BRED}Error: option '${YELLOW}--override-alias${BRED}' requires an argument.${RST}"
					command_install_help
					return 1
				fi
				;;
			-*)
				msg
				msg "${BRED}Error: got unknown option '${YELLOW}${1}${BRED}'.${RST}"
				command_install_help
				return 1
				;;
			*)
				if [ -z "${distro_name-}" ]; then
					if [ -z "$1" ]; then
						msg
						msg "${BRED}Error: distribution alias argument should not be empty.${RST}"
						command_install_help
						return 1
					fi
					distro_name="$1"
				else
					msg
					msg "${BRED}Error: got excessive positional argument '${YELLOW}${1}${BRED}'. Note that distribution can be specified only once.${RST}"
					command_install_help
					return 1
				fi
				;;
		esac
		shift 1
	done

	if [ -z "${distro_name-}" ]; then
		msg
		msg "${BRED}Error: distribution alias is not specified.${RST}"
		command_install_help
		return 1
	fi

	if [ -z "${SUPPORTED_DISTRIBUTIONS["$distro_name"]+x}" ]; then
		msg
		msg "${BRED}Error: unknown distribution '${YELLOW}${distro_name}${BRED}' was requested to be installed.${RST}"
		msg
		msg "${CYAN}View supported distributions by: ${GREEN}${PROGRAM_NAME} list${RST}"
		msg
		return 1
	fi

	if [ -n "${override_alias-}" ]; then
		if [ ! -e "${DISTRO_PLUGINS_DIR}/${override_alias}.sh" ] && [ ! -e "${DISTRO_PLUGINS_DIR}/${override_alias}.override.sh" ]; then
			msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Creating file '${DISTRO_PLUGINS_DIR}/${override_alias}.override.sh'...${RST}"
			distro_plugin_script="${DISTRO_PLUGINS_DIR}/${override_alias}.override.sh"
			cp "${DISTRO_PLUGINS_DIR}/${distro_name}.sh" "${distro_plugin_script}"
			sed -i "s/^\(DISTRO_NAME=\)\(.*\)\$/\1\"${SUPPORTED_DISTRIBUTIONS["$distro_name"]} - ${override_alias}\"/g" "${distro_plugin_script}"
			SUPPORTED_DISTRIBUTIONS["${override_alias}"]="${SUPPORTED_DISTRIBUTIONS["$distro_name"]}"
			distro_name="${override_alias}"
		else
			msg
			msg "${BRED}Error: distribution with alias '${YELLOW}${override_alias}${BRED}' already exists.${RST}"
			msg
			return 1
		fi
	else
		distro_plugin_script="${DISTRO_PLUGINS_DIR}/${distro_name}.sh"

		# Try an alternate distribution name.
		if [ ! -f "${distro_plugin_script}" ]; then
			distro_plugin_script="${DISTRO_PLUGINS_DIR}/${distro_name}.override.sh"
		fi
	fi

	if [ -d "${INSTALLED_ROOTFS_DIR}/${distro_name}" ]; then
		msg
		msg "${BRED}Error: distribution '${YELLOW}${distro_name}${BRED}' is already installed.${RST}"
		msg
		msg "${CYAN}Log in:     ${GREEN}${PROGRAM_NAME} login ${distro_name}${RST}"
		msg "${CYAN}Reinstall:  ${GREEN}${PROGRAM_NAME} reset ${distro_name}${RST}"
		msg "${CYAN}Uninstall:  ${GREEN}${PROGRAM_NAME} remove ${distro_name}${RST}"
		msg
		return 1
	fi

	if [ -f "${distro_plugin_script}" ]; then
		msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Installing ${YELLOW}${SUPPORTED_DISTRIBUTIONS["$distro_name"]}${CYAN}...${RST}"

		# Make sure things are cleared up on failure or user requested exit.
		# shellcheck disable=SC2064 # variables must expand here
		trap "echo -e \"\\r\\e[2K${BLUE}[${RED}!${BLUE}] ${CYAN}Exiting due to failure.${RST}\"; chmod -R u+rwx \"${INSTALLED_ROOTFS_DIR:?}/${distro_name:?}\"; rm -rf \"${INSTALLED_ROOTFS_DIR:?}/${distro_name:?}\"; [ -e \"${DISTRO_PLUGINS_DIR}/${distro_name}.override.sh\" ] && rm -f \"${DISTRO_PLUGINS_DIR}/${distro_name}.override.sh\"; exit 1;" EXIT
		# shellcheck disable=SC2064 # variables must expand here
		trap "trap - EXIT; echo -e \"\\r\\e[2K${BLUE}[${RED}!${BLUE}] ${CYAN}Exiting immediately as requested.${RST}\"; chmod -R u+rwx \"${INSTALLED_ROOTFS_DIR:?}/${distro_name:?}\"; rm -rf \"${INSTALLED_ROOTFS_DIR:?}/${distro_name:?}\"; [ -e \"${DISTRO_PLUGINS_DIR}/${distro_name}.override.sh\" ] && rm -f \"${DISTRO_PLUGINS_DIR}/${distro_name}.override.sh\"; exit 1;" HUP INT TERM

		msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Creating directory '${INSTALLED_ROOTFS_DIR}/${distro_name}'...${RST}"
		mkdir -p "${INSTALLED_ROOTFS_DIR}/${distro_name}"

		export PROOT_L2S_DIR="${INSTALLED_ROOTFS_DIR}/${distro_name}/.l2s"
		if [ ! -d "${INSTALLED_ROOTFS_DIR}/${distro_name}/.l2s" ]; then
			echo -e "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Creating directory '${PROOT_L2S_DIR}'...${RST}"
			mkdir -p "$PROOT_L2S_DIR"
		fi

		# This will define logic for handling the distribution.
		# Possible values for now: normal, termux.
		DISTRO_TYPE="normal"

		# This should be overridden in distro plug-in with valid URL for
		# each architecture where possible.
		TARBALL_URL["aarch64"]=""
		TARBALL_URL["arm"]=""
		TARBALL_URL["i686"]=""
		TARBALL_URL["riscv64"]=""
		TARBALL_URL["x86_64"]=""

		# This should be overridden in distro plug-in with valid SHA-256
		# for corresponding archives.
		TARBALL_SHA256["aarch64"]=""
		TARBALL_SHA256["arm"]=""
		TARBALL_SHA256["i686"]=""
		TARBALL_SHA256["riscv64"]=""
		TARBALL_SHA256["x86_64"]=""

		# If your content inside archive isn't stored in subdirectory,
		# you can override this variable in distro plug-in with 0.
		TARBALL_STRIP_OPT=1

		# Distribution plug-in contains steps on how to get download URL
		# and further post-installation configuration.
		# shellcheck disable=SC1090
		source "${distro_plugin_script}"

		# Exit with error if specified distribution type is unknown
		case "${DISTRO_TYPE}" in
			normal|termux);;
			*)
				msg "${BLUE}[${RED}!${BLUE}] ${CYAN}The distribution has unsupported type '${DISTRO_TYPE}'.${RST}"
				return 1
				;;
		esac

		# If user wants custom download URL
		if [ -n "${PD_OVERRIDE_TARBALL_URL-}" ]; then
			TARBALL_URL["$DISTRO_ARCH"]="${PD_OVERRIDE_TARBALL_URL}"
			TARBALL_SHA256["$DISTRO_ARCH"]="${PD_OVERRIDE_TARBALL_SHA256}"
		fi
		if [ -n "${PD_OVERRIDE_TARBALL_STRIP_OPT-}" ]; then
			TARBALL_STRIP_OPT="${PD_OVERRIDE_TARBALL_STRIP_OPT}"
		fi

		# Cannot proceed without URL and SHA-256.
		if [ -z "${TARBALL_URL["$DISTRO_ARCH"]}" ]; then
			msg "${BLUE}[${RED}!${BLUE}] ${CYAN}The distribution download URL is not defined for CPU architecture '${DISTRO_ARCH}'.${RST}"
			return 1
		fi
		# But SHA-256 should be ignored for custom URLs if another SHA-256 is not given.
		if [ -z "${PD_OVERRIDE_TARBALL_URL-}" ] && [ -n "${PD_OVERRIDE_TARBALL_SHA256-}" ]; then
			if ! grep -qP '^[0-9a-fA-F]{64}$' <<< "${TARBALL_SHA256["$DISTRO_ARCH"]}"; then
				msg
				msg "${BRED}Error: got malformed SHA-256 from plug-in script '${distro_plugin_script}'.${RST}"
				msg
				return 1
			fi
		fi

		if [ ! -d "$DOWNLOAD_CACHE_DIR" ]; then
			msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Creating directory '$DOWNLOAD_CACHE_DIR'...${RST}"
			mkdir -p "$DOWNLOAD_CACHE_DIR"
		fi

		local archive_name
		archive_name=$(basename "${TARBALL_URL["$DISTRO_ARCH"]}")

		if [ ! -f "${DOWNLOAD_CACHE_DIR}/${archive_name}" ]; then
			msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Downloading rootfs archive...${RST}"
			msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}URL: ${TARBALL_URL["$DISTRO_ARCH"]}${RST}"

			# Using temporary file as script can't distinguish the partially
			# downloaded file from the complete. Useful in case if curl will
			# fail for some reason.
			msg
			rm -f "${DOWNLOAD_CACHE_DIR}/${archive_name}.tmp"
			if ! curl --disable --fail --retry 5 --retry-connrefused --retry-delay 5 --location \
				--output "${DOWNLOAD_CACHE_DIR}/${archive_name}.tmp" "${TARBALL_URL["$DISTRO_ARCH"]}"; then
				msg
				msg "${BLUE}[${RED}!${BLUE}] ${CYAN}Download failure, please check your network connection.${RST}"
				rm -f "${DOWNLOAD_CACHE_DIR}/${archive_name}.tmp"
				return 1
			fi
			msg

			# If curl finished successfully, rename file to original.
			mv -f "${DOWNLOAD_CACHE_DIR}/${archive_name}.tmp" "${DOWNLOAD_CACHE_DIR}/${archive_name}"
		else
			msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Using cached rootfs archive...${RST}"
		fi

		if [ -n "${TARBALL_SHA256["$DISTRO_ARCH"]}" ]; then
			msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Checking integrity, please wait...${RST}"
			local actual_sha256
			actual_sha256=$(sha256sum "${DOWNLOAD_CACHE_DIR}/${archive_name}" | awk '{ print $1}')

			if [ "${TARBALL_SHA256["$DISTRO_ARCH"]}" != "${actual_sha256}" ]; then
				msg "${BLUE}[${RED}!${BLUE}] ${CYAN}Integrity checking failed. Try to redo installation again.${RST}"
				rm -f "${DOWNLOAD_CACHE_DIR}/${archive_name}"
				return 1
			fi
		else
			msg "${BLUE}[${RED}!${BLUE}] ${CYAN}Integrity checking of downloaded rootfs has been disabled.${RST}"
		fi

		msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Extracting rootfs, please wait...${RST}"

		if [ "${DISTRO_TYPE}" = "termux" ]; then
			mkdir -p "${INSTALLED_ROOTFS_DIR}/${distro_name}/data/data/com.termux/files/home"
			if [ "$(file --brief --mime-type "${DOWNLOAD_CACHE_DIR}/${archive_name}")" = "application/zip" ]; then
				# Termux uses plain ZIP archive to deliver bootstrap environment.
				# It contains only directories and files. Access modes typically
				# recorded within the archive too.
				unzip -q -d "${INSTALLED_ROOTFS_DIR}/${distro_name}/data/data/com.termux/files/usr" \
					"${DOWNLOAD_CACHE_DIR}/${archive_name}"
			else
				# Fall back to tar if format isn't zip.
				mkdir -p "${INSTALLED_ROOTFS_DIR}/${distro_name}/data/data/com.termux/files/usr"
				tar -C "${INSTALLED_ROOTFS_DIR}/${distro_name}/data/data/com.termux/files/usr" \
					--warning=no-unknown-keyword --delay-directory-restore \
					--preserve-permissions --strip="${TARBALL_STRIP_OPT}" \
					-xf "${DOWNLOAD_CACHE_DIR}/${archive_name}"
			fi

			local cur_wd=$(pwd)
			cd "${INSTALLED_ROOTFS_DIR}/${distro_name}/data/data/com.termux/files/usr"

			# Symlinks must be manually restored using instructions from
			# file 'SYMLINKS.txt'.
			if [ -f "./SYMLINKS.txt" ]; then
				msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Creating symlinks, please wait...${RST}"
				cat SYMLINKS.txt | while IFS='←' read -r src dst; do
					ln -s "$src" "$dst"
				done
				rm -f "./SYMLINKS.txt"
			fi

			cd "$cur_wd"

			if [ -f "${INSTALLED_ROOTFS_DIR}/${distro_name}/data/data/com.termux/files/usr/etc/bash.bashrc" ]; then
				msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Updating PS1 in bash.bashrc...${RST}"
				echo '# Added by proot-distro:' >> \
					"${INSTALLED_ROOTFS_DIR}/${distro_name}/data/data/com.termux/files/usr/etc/bash.bashrc"
				echo 'PS1="\\[\\e[0;35m\\]\\\PD\\\\\[\\e[0m\\] ${PS1}"' >> \
					"${INSTALLED_ROOTFS_DIR}/${distro_name}/data/data/com.termux/files/usr/etc/bash.bashrc"
			fi
		else
			# Prevent possible conflicts with proot.
			unset LD_PRELOAD

			# --exclude='dev' - need to exclude /dev directory which may contain device files.
			# --delay-directory-restore - set directory permissions only when files were extracted
			#                             to avoid issues with Arch Linux bootstrap archives.
			set +e
			proot --link2symlink \
				tar -C "${INSTALLED_ROOTFS_DIR}/${distro_name}" --warning=no-unknown-keyword \
				--delay-directory-restore --preserve-permissions --strip="${TARBALL_STRIP_OPT}" \
				-xf "${DOWNLOAD_CACHE_DIR}/${archive_name}" --exclude='dev' |& grep -v "/linkerconfig/" >&2
			set -e

			# Restore LD_PRELOAD after proot.
			[ -n "$TERMUX_LDPRELOAD" ] && export LD_PRELOAD="$TERMUX_LDPRELOAD"

			# If no /etc in rootfs, terminate installation.
			# This usually indicates that downloaded distribution archive doesn't contain
			# actual rootfs, wrong tar strip option was specified or the distribution has
			# high grade of customization and doesn't respect FHS standard.
			if [ ! -e "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc" ]; then
				msg
				msg "${BRED}Error: the rootfs of distribution '${YELLOW}${distro_name}${BRED}' has unexpected structure (no /etc directory). Make sure that variable TARBALL_STRIP_OPT specified in distribution plug-in is correct.${RST}"
				msg
				return 1
			fi

			# Write important environment variables to /etc/environment.
			chmod u+rw "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/environment" >/dev/null 2>&1 || true
			msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Writing file '${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/environment'...${RST}"
			for var in ANDROID_ART_ROOT ANDROID_DATA ANDROID_I18N_ROOT ANDROID_ROOT \
				ANDROID_RUNTIME_ROOT ANDROID_TZDATA_ROOT BOOTCLASSPATH COLORTERM \
				DEX2OATBOOTCLASSPATH EXTERNAL_STORAGE; do
				set +u
				if [ -n "${!var}" ]; then
					echo "${var}=${!var}" >> "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/environment"
				fi
				set -u
			done
			unset var
			# Don't touch these variables.
			# TERM is being inherited from currect environment. Otherwise it is being
			# set to xterm-256color (Termux app default).
			cat <<- EOF >> "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/environment"
			LANG=en_US.UTF-8
			MOZ_FAKE_NO_SANDBOX=1
			PATH=${DEFAULT_PATH_ENV}
			PULSE_SERVER=127.0.0.1
			TERM=${TERM-xterm-256color}
			TMPDIR=/tmp
			EOF

			# Fix PATH in some configuration files.
			for f in /etc/bash.bashrc /etc/profile /etc/login.defs; do
				[ ! -e "${INSTALLED_ROOTFS_DIR}/${distro_name}${f}" ] && continue
				msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Updating PATH in '${INSTALLED_ROOTFS_DIR}/${distro_name}${f}' if needed...${RST}"
				sed -i -E "s@\<(PATH=)(\"?[^\"[:space:]]+(\"|\$|\>))@\1\"${DEFAULT_PATH_ENV}\"@g" \
					"${INSTALLED_ROOTFS_DIR}/${distro_name}${f}"
			done
			unset f

			# Default /etc/resolv.conf may be empty or unsuitable for use.
			msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Creating file '${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/resolv.conf'...${RST}"
			rm -f "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/resolv.conf"
			cat <<- EOF > "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/resolv.conf"
			nameserver ${DEFAULT_PRIMARY_NAMESERVER}
			nameserver ${DEFAULT_SECONDARY_NAMESERVER}
			EOF

			# Default /etc/hosts may be empty or incomplete.
			msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Creating file '${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/hosts'...${RST}"
			chmod u+rw "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/hosts" >/dev/null 2>&1 || true
			cat <<- EOF > "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/hosts"
			# IPv4.
			127.0.0.1   localhost.localdomain localhost

			# IPv6.
			::1         localhost.localdomain localhost ip6-localhost ip6-loopback
			fe00::0     ip6-localnet
			ff00::0     ip6-mcastprefix
			ff02::1     ip6-allnodes
			ff02::2     ip6-allrouters
			ff02::3     ip6-allhosts
			EOF

			# Add Android-specific UIDs/GIDs to /etc/group and /etc/gshadow.
			msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Registering Android-specific UIDs and GIDs...${RST}"
			chmod u+rw "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/passwd" \
				"${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/shadow" \
				"${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/group" \
				"${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/gshadow" >/dev/null 2>&1 || true
			echo "aid_$(id -un):x:$(id -u):$(id -g):Termux:/:/sbin/nologin" >> \
				"${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/passwd"
			echo "aid_$(id -un):*:18446:0:99999:7:::" >> \
				"${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/shadow"
			local group_name group_id
			while read -r group_name group_id; do
				echo "aid_${group_name}:x:${group_id}:root,aid_$(id -un)" \
					>> "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/group"
				if [ -f "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/gshadow" ]; then
					echo "aid_${group_name}:*::root,aid_$(id -un)" \
						>> "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/gshadow"
				fi
			done < <(paste <(id -Gn | tr ' ' '\n') <(id -G | tr ' ' '\n'))

			# Ensure that proot will be able to bind fake /proc and /sys entries.
			setup_fake_sysdata
		fi

		# Run optional distro-specific hook.
		if declare -f -F distro_setup >/dev/null 2>&1; then
			msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Running distribution-specific configuration steps...${RST}"
			(cd "${INSTALLED_ROOTFS_DIR}/${distro_name}"
				distro_setup
			)
		fi

		# Reset trap for HUP/INT/TERM.
		trap - EXIT
		trap 'echo -e "\\r\\e[2K${BLUE}[${RED}!${BLUE}] ${CYAN}Exiting immediately as requested.${RST}"; exit 1;' HUP INT TERM

		msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Finished.${RST}"
		msg
		msg "${CYAN}Log in with: ${GREEN}${PROGRAM_NAME} login ${distro_name}${CYAN}${RST}"
		msg
		return 0
	else
		# Reset trap for HUP/INT/TERM.
		trap - EXIT
		trap 'echo -e "\\r\\e[2K${BLUE}[${RED}!${BLUE}] ${CYAN}Exiting immediately as requested.${RST}"; exit 1;' HUP INT TERM

		msg "${BLUE}[${RED}!${BLUE}] ${CYAN}Cannot find '${distro_plugin_script}' which is used to define a distribution properties.${RST}"
		return 1
	fi
}

# Special function for executing a command inside rootfs.
# Intended to be used inside plug-in distro_setup() function.
# shellcheck disable=SC2317 # run_proot_cmd called indirectly
run_proot_cmd() {
	if [ -z "${distro_name-}" ]; then
		msg
		msg "${BRED}Error: called run_proot_cmd() but \${distro_name} is not set. Make sure that run_proot_cmd() is used inside distro_setup() function.${RST}"
		msg
		return 1
	fi

	if [ -z "${DISTRO_ARCH-}" ]; then
		msg
		msg "${BRED}Error: called run_proot_cmd() but \${DISTRO_ARCH} is not set.${RST}"
		msg
		return 1
	fi

	local cpu_emulator_arg=""
	if [ "$DISTRO_ARCH" != "$DEVICE_CPU_ARCH" ]; then
		local cpu_emulator_path=""

		# If CPU and host OS are 64bit, we can run 32bit guest OS without emulation.
		# Everything else requires emulator (QEMU).
		case "$DISTRO_ARCH" in
			aarch64) cpu_emulator_path="@TERMUX_PREFIX@/bin/qemu-aarch64";;
			arm)
				if [ "$DEVICE_CPU_ARCH" != "aarch64" ] || ! $SUPPORT_32BIT; then
					cpu_emulator_path="@TERMUX_PREFIX@/bin/qemu-arm"
				fi
				;;
			i686)
				if [ "$DEVICE_CPU_ARCH" != "x86_64" ]; then
					cpu_emulator_path="@TERMUX_PREFIX@/bin/qemu-i386"
				fi
				;;
			riscv64) cpu_emulator_path="@TERMUX_PREFIX@/bin/qemu-riscv64";;
			x86_64)
				if [ "$PROOT_DISTRO_X64_EMULATOR" = "QEMU" ]; then
					cpu_emulator_path="@TERMUX_PREFIX@/bin/qemu-x86_64"
				elif [ "$PROOT_DISTRO_X64_EMULATOR" = "BLINK" ]; then
					cpu_emulator_path="@TERMUX_PREFIX@/bin/blink"
				else
					msg
					msg "${BRED}Error: PROOT_DISTRO_X64_EMULATOR has unknown value '$PROOT_DISTRO_X64_EMULATOR'. Valid values are: BLINK, QEMU."
					msg
				fi
				;;
			*)
				msg
				msg "${BRED}Error: DISTRO_ARCH has unknown value '$DISTRO_ARCH'. Valid values are: aarch64, arm, i686, riscv64, x86_64."
				msg
				return 1
			;;
		esac

		if [ -n "$cpu_emulator_path" ]; then
			if [ -x "$cpu_emulator_path" ]; then
				cpu_emulator_arg="-q ${cpu_emulator_path}"
			else
				local cpu_emulator_pkg=""
				case "$DISTRO_ARCH" in
					aarch64) cpu_emulator_pkg="qemu-user-aarch64";;
					arm) cpu_emulator_pkg="qemu-user-arm";;
					i686) cpu_emulator_pkg="qemu-user-i386";;
					riscv64) cpu_emulator_pkg="qemu-user-riscv64";;
					x86_64)
						if [ "$PROOT_DISTRO_X64_EMULATOR" = "QEMU" ]; then
							cpu_emulator_pkg="qemu-user-x86-64"
						elif [ "$PROOT_DISTRO_X64_EMULATOR" = "BLINK" ]; then
							cpu_emulator_pkg="blink"
						else
							msg
							msg "${BRED}Error: PROOT_DISTRO_X64_EMULATOR has unknown value '$PROOT_DISTRO_X64_EMULATOR'. Valid values are: BLINK, QEMU."
							msg
						fi
						;;
					*) cpu_emulator_pkg="qemu-user-${DISTRO_ARCH}";;
				esac
				msg
				msg "${BRED}Error: package '${cpu_emulator_pkg}' is not installed.${RST}"
				msg
				return 1
			fi
		fi
	else
		# Warn about CPU not supporting 32-bit instructions
		if ! $SUPPORT_32BIT; then
			msg "${BRED}Warning: CPU doesn't support 32-bit instructions, some software may not work.${RST}"
		fi
	fi

	if [ -n "$cpu_emulator_arg" ]; then
		if [ -d "/apex" ]; then
			cpu_emulator_arg="${cpu_emulator_arg} --bind=/apex"
		fi
		if [ -e "/linkerconfig/ld.config.txt" ]; then
			cpu_emulator_arg="${cpu_emulator_arg} --bind=/linkerconfig/ld.config.txt"
		fi
		cpu_emulator_arg="${cpu_emulator_arg} --bind=@TERMUX_PREFIX@"
		cpu_emulator_arg="${cpu_emulator_arg} --bind=/system"
		cpu_emulator_arg="${cpu_emulator_arg} --bind=/vendor"
		if [ -f "/plat_property_contexts" ]; then
			cpu_emulator_arg="${cpu_emulator_arg} --bind=/plat_property_contexts"
		fi
		if [ -f "/property_contexts" ]; then
			cpu_emulator_arg="${cpu_emulator_arg} --bind=/property_contexts"
		fi
	fi

	if [ "${DISTRO_TYPE-normal}" = "termux" ]; then
		local -a extra_binds
		local system_mnt
		for system_mnt in /apex /odm /product /system /system_ext /vendor \
			/linkerconfig/ld.config.txt \
			/linkerconfig/com.android.art/ld.config.txt \
			/plat_property_contexts /property_contexts; do

			if [ -e "$system_mnt" ]; then
				system_mnt=$(realpath "$system_mnt")
			else
				continue
			fi

			if [ -d "$system_mnt" ]; then
				local dir_mode
				dir_mode=$(stat --format='%a' "$system_mnt")
				if [[ ${dir_mode:2} =~ ^[157]$ ]]; then
					extra_binds+=("--bind=${system_mnt}")
				fi
			elif [ -f "$system_mnt" ]; then
				if head -c 1 "$system_mnt" >/dev/null 2>&1; then
					extra_binds+=("--bind=${system_mnt}")
				fi
			else
				continue
			fi
		done

		# Prevent possible conflicts with proot.
		unset LD_PRELOAD

		# shellcheck disable=SC2086 # ${cpu_emulator_arg} should expand into nothing rather than into ''.
		proot ${cpu_emulator_arg} \
			-L \
			--kill-on-exit \
			--rootfs="${INSTALLED_ROOTFS_DIR}/${distro_name}" \
			--cwd=/ \
			--bind=/dev \
			--bind=/proc \
			--bind=/sys \
			"${extra_binds[@]}" \
			/data/data/com.termux/files/usr/bin/env \
			HOME="/data/data/com.termux/files/home" \
			PATH="/data/data/com.termux/files/usr/bin" \
			PREFIX="/data/data/com.termux/files/usr" \
			TMPDIR="/data/data/com.termux/files/usr/tmp" \
			"$@"

		# Restore LD_PRELOAD after proot.
		[ -n "$TERMUX_LDPRELOAD" ] && export LD_PRELOAD="$TERMUX_LDPRELOAD"
	else
		# Ensure that proot will be able to bind fake /proc and /sys entries.
		setup_fake_sysdata

		# With this tools should assume that no SELinux present.
		set -- "--bind=${INSTALLED_ROOTFS_DIR}/${distro_name}/sys/.empty:/sys/fs/selinux" "$@"

		# Prevent possible conflicts with proot.
		unset LD_PRELOAD

		# shellcheck disable=SC2086 # ${cpu_emulator_arg} should expand into nothing rather than into ''.
		proot ${cpu_emulator_arg} \
			-L \
			--kernel-release="${DEFAULT_FAKE_KERNEL_RELEASE}" \
			--link2symlink \
			--kill-on-exit \
			--rootfs="${INSTALLED_ROOTFS_DIR}/${distro_name}" \
			--root-id \
			--cwd=/root \
			--bind=/dev \
			--bind="/dev/urandom:/dev/random" \
			--bind=/proc \
			--bind="/proc/self/fd:/dev/fd" \
			--bind="/proc/self/fd/0:/dev/stdin" \
			--bind="/proc/self/fd/1:/dev/stdout" \
			--bind="/proc/self/fd/2:/dev/stderr" \
			--bind=/sys \
			--bind="${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.loadavg:/proc/loadavg" \
			--bind="${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.stat:/proc/stat" \
			--bind="${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.uptime:/proc/uptime" \
			--bind="${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.version:/proc/version" \
			--bind="${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.vmstat:/proc/vmstat" \
			--bind="${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.sysctl_entry_cap_last_cap:/proc/sys/kernel/cap_last_cap" \
			--bind="${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.sysctl_inotify_max_user_watches:/proc/sys/fs/inotify/max_user_watches" \
			--bind="${INSTALLED_ROOTFS_DIR}/${distro_name}/sys/.empty:/sys/fs/selinux" \
			/usr/bin/env -i \
				"HOME=/root" \
				"LANG=C.UTF-8" \
				"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin" \
				"TERM=${TERM-xterm-256color}" \
				"TMPDIR=/tmp" \
				"$@"

		# Restore LD_PRELOAD after proot.
		[ -n "$TERMUX_LDPRELOAD" ] && export LD_PRELOAD="$TERMUX_LDPRELOAD"
	fi
}

# A function for preparing fake content for certain system data interfaces
# which known to be restricted on Android OS.
#
# All /proc entries are based on values retrieved from Arch Linux (x86_64)
# running on a VM with 8 CPUs and 8 GiB of memory. Date 2023.03.28, Linux 6.2.1.
# Some values edited to fit the PRoot-Distro.
setup_fake_sysdata() {
	local d
	for d in proc sys sys/.empty; do
		if [ ! -e "${INSTALLED_ROOTFS_DIR}/${distro_name}/${d}" ]; then
			mkdir -p "${INSTALLED_ROOTFS_DIR}/${distro_name}/${d}"
		fi
		chmod 700 "${INSTALLED_ROOTFS_DIR}/${distro_name}/${d}"
	done
	unset d

	if [ ! -f "${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.loadavg" ]; then
		cat <<- EOF > "${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.loadavg"
		0.12 0.07 0.02 2/165 765
		EOF
	fi

	if [ ! -f "${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.stat" ]; then
		cat <<- EOF > "${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.stat"
		cpu  1957 0 2877 93280 262 342 254 87 0 0
		cpu0 31 0 226 12027 82 10 4 9 0 0
		cpu1 45 0 664 11144 21 263 233 12 0 0
		cpu2 494 0 537 11283 27 10 3 8 0 0
		cpu3 359 0 234 11723 24 26 5 7 0 0
		cpu4 295 0 268 11772 10 12 2 12 0 0
		cpu5 270 0 251 11833 15 3 1 10 0 0
		cpu6 430 0 520 11386 30 8 1 12 0 0
		cpu7 30 0 172 12108 50 8 1 13 0 0
		intr 127541 38 290 0 0 0 0 4 0 1 0 0 25329 258 0 5777 277 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
		ctxt 140223
		btime 1680020856
		processes 772
		procs_running 2
		procs_blocked 0
		softirq 75663 0 5903 6 25375 10774 0 243 11685 0 21677
		EOF
	fi

	if [ ! -f "${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.uptime" ]; then
		cat <<- EOF > "${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.uptime"
		124.08 932.80
		EOF
	fi

	if [ ! -f "${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.version" ]; then
		cat <<- EOF > "${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.version"
		Linux version ${DEFAULT_FAKE_KERNEL_RELEASE} (proot@termux) (gcc (GCC) 13.3.0, GNU ld (GNU Binutils) 2.42) ${DEFAULT_FAKE_KERNEL_VERSION}
		EOF
	fi

	if [ ! -f "${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.vmstat" ]; then
		cat <<- EOF > "${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.vmstat"
		nr_free_pages 1743136
		nr_zone_inactive_anon 179281
		nr_zone_active_anon 7183
		nr_zone_inactive_file 22858
		nr_zone_active_file 51328
		nr_zone_unevictable 642
		nr_zone_write_pending 0
		nr_mlock 0
		nr_bounce 0
		nr_zspages 0
		nr_free_cma 0
		numa_hit 1259626
		numa_miss 0
		numa_foreign 0
		numa_interleave 720
		numa_local 1259626
		numa_other 0
		nr_inactive_anon 179281
		nr_active_anon 7183
		nr_inactive_file 22858
		nr_active_file 51328
		nr_unevictable 642
		nr_slab_reclaimable 8091
		nr_slab_unreclaimable 7804
		nr_isolated_anon 0
		nr_isolated_file 0
		workingset_nodes 0
		workingset_refault_anon 0
		workingset_refault_file 0
		workingset_activate_anon 0
		workingset_activate_file 0
		workingset_restore_anon 0
		workingset_restore_file 0
		workingset_nodereclaim 0
		nr_anon_pages 7723
		nr_mapped 8905
		nr_file_pages 253569
		nr_dirty 0
		nr_writeback 0
		nr_writeback_temp 0
		nr_shmem 178741
		nr_shmem_hugepages 0
		nr_shmem_pmdmapped 0
		nr_file_hugepages 0
		nr_file_pmdmapped 0
		nr_anon_transparent_hugepages 1
		nr_vmscan_write 0
		nr_vmscan_immediate_reclaim 0
		nr_dirtied 0
		nr_written 0
		nr_throttled_written 0
		nr_kernel_misc_reclaimable 0
		nr_foll_pin_acquired 0
		nr_foll_pin_released 0
		nr_kernel_stack 2780
		nr_page_table_pages 344
		nr_sec_page_table_pages 0
		nr_swapcached 0
		pgpromote_success 0
		pgpromote_candidate 0
		nr_dirty_threshold 356564
		nr_dirty_background_threshold 178064
		pgpgin 890508
		pgpgout 0
		pswpin 0
		pswpout 0
		pgalloc_dma 272
		pgalloc_dma32 261
		pgalloc_normal 1328079
		pgalloc_movable 0
		pgalloc_device 0
		allocstall_dma 0
		allocstall_dma32 0
		allocstall_normal 0
		allocstall_movable 0
		allocstall_device 0
		pgskip_dma 0
		pgskip_dma32 0
		pgskip_normal 0
		pgskip_movable 0
		pgskip_device 0
		pgfree 3077011
		pgactivate 0
		pgdeactivate 0
		pglazyfree 0
		pgfault 176973
		pgmajfault 488
		pglazyfreed 0
		pgrefill 0
		pgreuse 19230
		pgsteal_kswapd 0
		pgsteal_direct 0
		pgsteal_khugepaged 0
		pgdemote_kswapd 0
		pgdemote_direct 0
		pgdemote_khugepaged 0
		pgscan_kswapd 0
		pgscan_direct 0
		pgscan_khugepaged 0
		pgscan_direct_throttle 0
		pgscan_anon 0
		pgscan_file 0
		pgsteal_anon 0
		pgsteal_file 0
		zone_reclaim_failed 0
		pginodesteal 0
		slabs_scanned 0
		kswapd_inodesteal 0
		kswapd_low_wmark_hit_quickly 0
		kswapd_high_wmark_hit_quickly 0
		pageoutrun 0
		pgrotated 0
		drop_pagecache 0
		drop_slab 0
		oom_kill 0
		numa_pte_updates 0
		numa_huge_pte_updates 0
		numa_hint_faults 0
		numa_hint_faults_local 0
		numa_pages_migrated 0
		pgmigrate_success 0
		pgmigrate_fail 0
		thp_migration_success 0
		thp_migration_fail 0
		thp_migration_split 0
		compact_migrate_scanned 0
		compact_free_scanned 0
		compact_isolated 0
		compact_stall 0
		compact_fail 0
		compact_success 0
		compact_daemon_wake 0
		compact_daemon_migrate_scanned 0
		compact_daemon_free_scanned 0
		htlb_buddy_alloc_success 0
		htlb_buddy_alloc_fail 0
		cma_alloc_success 0
		cma_alloc_fail 0
		unevictable_pgs_culled 27002
		unevictable_pgs_scanned 0
		unevictable_pgs_rescued 744
		unevictable_pgs_mlocked 744
		unevictable_pgs_munlocked 744
		unevictable_pgs_cleared 0
		unevictable_pgs_stranded 0
		thp_fault_alloc 13
		thp_fault_fallback 0
		thp_fault_fallback_charge 0
		thp_collapse_alloc 4
		thp_collapse_alloc_failed 0
		thp_file_alloc 0
		thp_file_fallback 0
		thp_file_fallback_charge 0
		thp_file_mapped 0
		thp_split_page 0
		thp_split_page_failed 0
		thp_deferred_split_page 1
		thp_split_pmd 1
		thp_scan_exceed_none_pte 0
		thp_scan_exceed_swap_pte 0
		thp_scan_exceed_share_pte 0
		thp_split_pud 0
		thp_zero_page_alloc 0
		thp_zero_page_alloc_failed 0
		thp_swpout 0
		thp_swpout_fallback 0
		balloon_inflate 0
		balloon_deflate 0
		balloon_migrate 0
		swap_ra 0
		swap_ra_hit 0
		ksm_swpin_copy 0
		cow_ksm 0
		zswpin 0
		zswpout 0
		direct_map_level2_splits 29
		direct_map_level3_splits 0
		nr_unstable 0
		EOF
	fi

	if [ ! -f "${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.sysctl_entry_cap_last_cap" ]; then
		cat <<- EOF > "${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.sysctl_entry_cap_last_cap"
		40
		EOF
	fi

	if [ ! -f "${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.sysctl_inotify_max_user_watches" ]; then
		cat <<- EOF > "${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.sysctl_inotify_max_user_watches"
		4096
		EOF
	fi
}

command_install_help() {
	msg
	msg "${BYELLOW}Usage: ${BCYAN}${PROGRAM_NAME} ${GREEN}install ${CYAN}[${GREEN}OPTIONS${CYAN}] [${GREEN}DISTRIBUTION ALIAS${CYAN}]${RST}"
	msg
	msg "${CYAN}Command aliases: ${GREEN}add${CYAN}, ${GREEN}i${CYAN}, ${GREEN}in${CYAN}, ${GREEN}ins${RST}"
	msg
	msg "${CYAN}Install a specified Linux distribution.${RST}"
	msg
	msg "${CYAN}Options:${RST}"
	msg
	msg "  ${GREEN}--help                         ${CYAN}- Show this help information.${RST}"
	msg
	msg "  ${GREEN}--override-alias [new alias]   ${CYAN}- Set a custom alias for installed${RST}"
	msg "                                   ${CYAN}distribution.${RST}"
	msg
	msg "${CYAN}In case you want to use a custom rootfs download source (mirror),${RST}"
	msg "${CYAN}specify environment variable '${GREEN}PD_OVERRIDE_TARBALL_URL${CYAN}' as below:${RST}"
	msg
	msg "  ${GREEN}export PD_OVERRIDE_TARBALL_URL=\"http://localhost:8080/dist.tar.gz\"${RST}"
	msg "  ${GREEN}proot-distro install <alias>${RST}"
	msg
	msg "${CYAN}Optionally specify '${GREEN}PD_OVERRIDE_TARBALL_STRIP_OPT${CYAN}' to define how${RST}"
	msg "${CYAN}many path components need to be stripped while extracting rootfs.${RST}"
	msg "${CYAN}Default is 1. Specify 0 if rootfs was not stored in a sub directory.${RST}"
	msg
	msg "${CYAN}Selected distribution should be referenced by alias which can be${RST}"
	msg "${CYAN}obtained by this command: ${GREEN}${PROGRAM_NAME} list${RST}"
	msg
	show_version
	msg
}

#############################################################################
#
# FUNCTION TO UNINSTALL SPECIFIED DISTRIBUTION
#
# Delete the rootfs of given distribution. If the associated plug-in has
# extension '.override.sh', it will be deleted as well.
#
#############################################################################

command_remove() {
	local distro_name

	while (($# >= 1)); do
		case "$1" in
			-h|--help)
				command_remove_help
				return 0
				;;
			-*)
				msg
				msg "${BRED}Error: got unknown option '${YELLOW}${1}${BRED}'.${RST}"
				command_remove_help
				return 1
				;;
			*)
				if [ -z "${distro_name-}" ]; then
					if [ -z "$1" ]; then
						msg
						msg "${BRED}Error: distribution alias argument should not be empty.${RST}"
						command_remove_help
						return 1
					fi
					distro_name="$1"
				else
					msg
					msg "${BRED}Error: got excessive positional argument '${YELLOW}${1}${BRED}'. Note that distribution can be specified only once.${RST}"
					command_remove_help
					return 1
				fi
				;;
		esac
		shift 1
	done

	if [ -z "${distro_name-}" ]; then
		msg
		msg "${BRED}Error: distribution alias is not specified.${RST}"
		command_remove_help
		return 1
	fi

	if [ -z "${SUPPORTED_DISTRIBUTIONS["$distro_name"]+x}" ]; then
		msg
		msg "${BRED}Error: unknown distribution '${YELLOW}${distro_name}${BRED}' was requested to be removed.${RST}"
		msg
		msg "${CYAN}View supported distributions by: ${GREEN}${PROGRAM_NAME} list${RST}"
		msg
		return 1
	fi

	if [ ! -d "${INSTALLED_ROOTFS_DIR}/${distro_name}" ]; then
		msg
		msg "${BRED}Error: distribution '${YELLOW}${distro_name}${BRED}' is not installed.${RST}"
		msg
		return 1
	fi

	# The plug-ins created during renaming the distribution are considered
	# as generated content and should be deleted with rootfs.
	if [ "${CMD_REMOVE_REQUESTED_RESET-false}" = "false" ] && [ -e "${DISTRO_PLUGINS_DIR}/${distro_name}.override.sh" ]; then
		msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Deleting file '${DISTRO_PLUGINS_DIR}/${distro_name}.override.sh'...${RST}"
		rm -f "${DISTRO_PLUGINS_DIR}/${distro_name}.override.sh"
	fi

	msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Wiping the rootfs of ${YELLOW}${SUPPORTED_DISTRIBUTIONS["$distro_name"]}${CYAN}...${RST}"
	# Attempt to restore permissions so directory can be removed without issues.
	chmod u+rwx -R "${INSTALLED_ROOTFS_DIR}/${distro_name}" > /dev/null 2>&1 || true
	# There is still chance for failure.
	if rm -rf "${INSTALLED_ROOTFS_DIR:?}/${distro_name:?}"; then
		msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Finished.${RST}"
	else
		msg "${BLUE}[${RED}!${BLUE}] ${CYAN}Finished with errors. Some files probably were not deleted.${RST}"
		return 1
	fi
}

command_remove_help() {
	msg
	msg "${BYELLOW}Usage: ${BCYAN}${PROGRAM_NAME} ${GREEN}remove ${CYAN}[${GREEN}DISTRIBUTION ALIAS${CYAN}]${RST}"
	msg
	msg "${CYAN}Command aliases: ${GREEN}rm${RST}"
	msg
	msg "${CYAN}Remove a specified Linux distribution.${RST}"
	msg
	msg "${CYAN}Options:${RST}"
	msg
	msg "  ${GREEN}--help               ${CYAN}- Show this help information.${RST}"
	msg
	msg "${CYAN}Be careful when using it because you will not be prompted for${RST}"
	msg "${CYAN}confirmation and all data saved within the distribution will${RST}"
	msg "${CYAN}instantly gone.${RST}"
	msg
	msg "${CYAN}Selected distribution should be referenced by alias which can be${RST}"
	msg "${CYAN}obtained by this command: ${GREEN}${PROGRAM_NAME} list${RST}"
	msg
	show_version
	msg
}

#############################################################################
#
# FUNCTION TO RENAME A DISTRIBUTION
#
# Change the name of installed distribution by moving its rootfs directory
# and creating copy of original distrubution plug-in. The new plug-in will
# have an extension '.override.sh'.
#
#############################################################################

command_rename() {
	local orig_distro_name
	local new_distro_name

	while (($# >= 1)); do
		case "$1" in
			-h|--help)
				command_rename_help
				return 0
				;;
			-*)
				msg
				msg "${BRED}Error: got unknown option '${YELLOW}${1}${BRED}'.${RST}"
				command_rename_help
				return 1
				;;
			*)
				if [ -z "${orig_distro_name-}" ]; then
					if [ -z "$1" ]; then
						msg
						msg "${BRED}Error: original distribution alias argument should not be empty.${RST}"
						command_rename_help
						return 1
					fi
					orig_distro_name="$1"
				elif [ -z "${new_distro_name-}" ]; then
					if [ -z "$1" ]; then
						msg
						msg "${BRED}Error: new distribution alias argument should not be empty.${RST}"
						command_rename_help
						return 1
					fi
					new_distro_name="$1"
				else
					msg
					msg "${BRED}Error: got excessive positional argument '${YELLOW}${1}${BRED}'.${RST}"
					command_rename_help
					return 1
				fi
				;;
		esac
		shift 1
	done

	if [ -z "${orig_distro_name-}" ]; then
		msg
		msg "${BRED}Error: the original alias of distribution is not specified.${RST}"
		command_rename_help
		return 1
	fi

	if [ -z "${new_distro_name-}" ]; then
		msg
		msg "${BRED}Error: the new alias of distribution is not specified.${RST}"
		command_rename_help
		return 1
	fi

	if [ "${orig_distro_name}" = "${new_distro_name}" ]; then
		msg
		msg "${BRED}Error: the original and new distribution aliases should not be same.${RST}"
		command_rename_help
		return 1
	fi

	# Put a restriction on characters in distribution name.
	# Same as for --override-alias option of command_install().
	if ! grep -qP '^[a-z0-9][a-z0-9_.+\-]*$' <<< "${new_distro_name}"; then
		msg
		msg "${BRED}Error: the new alias of distribution should start only with an alphanumeric character and consist of alphanumeric characters including symbols '_.+-'.${RST}"
		command_rename_help
		return 1
	fi

	if grep -qP '^.*\.sh$' <<< "${new_distro_name}"; then
		msg
		msg "${BRED}Error: the new alias of distribution should not end with '.sh'.${RST}"
		msg
		return 1
	fi

	if [ -z "${SUPPORTED_DISTRIBUTIONS["$orig_distro_name"]+x}" ]; then
		msg
		msg "${BRED}Error: unknown distribution '${YELLOW}${orig_distro_name}${BRED}' was requested to be renamed.${RST}"
		msg
		msg "${CYAN}View supported distributions by: ${GREEN}${PROGRAM_NAME} list${RST}"
		msg
		return 1
	fi

	if [ ! -d "${INSTALLED_ROOTFS_DIR}/${orig_distro_name}" ]; then
		msg
		msg "${BRED}Error: cannot rename because the distribution '${YELLOW}${orig_distro_name}${BRED}' is not installed.${RST}"
		msg
		return 1
	fi

	if [ -d "${INSTALLED_ROOTFS_DIR}/${new_distro_name}" ]; then
		msg
		msg "${BRED}Error: cannot rename because the rootfs directory for distribution '${YELLOW}${new_distro_name}${BRED}' already exists.${RST}"
		msg
		return 1
	fi

	if [ -e "${DISTRO_PLUGINS_DIR}/${new_distro_name}.sh" ] || [ -e "${DISTRO_PLUGINS_DIR}/${new_distro_name}.override.sh" ]; then
		msg
		msg "${BRED}Error: distribution with alias '${YELLOW}${new_distro_name}${BRED}' already exists.${RST}"
		msg
		return 1
	fi

	if [ -e "${DISTRO_PLUGINS_DIR}/${orig_distro_name}.override.sh" ]; then
		msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Renaming '${DISTRO_PLUGINS_DIR}/${orig_distro_name}.override.sh' to '${DISTRO_PLUGINS_DIR}/${new_distro_name}.override.sh'...${RST}"
		mv "${DISTRO_PLUGINS_DIR}/${orig_distro_name}.override.sh" "${DISTRO_PLUGINS_DIR}/${new_distro_name}.override.sh"
		sed -i "s/^\(DISTRO_NAME=\)\"\(.*\) - ${orig_distro_name}\"\$/\1\"\2 - ${new_distro_name}\"/g" "${DISTRO_PLUGINS_DIR}/${new_distro_name}.override.sh"
	elif [ -e "${DISTRO_PLUGINS_DIR}/${orig_distro_name}.sh" ]; then
		msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Creating file '${DISTRO_PLUGINS_DIR}/${new_distro_name}.override.sh'...${RST}"
		cp "${DISTRO_PLUGINS_DIR}/${orig_distro_name}.sh" "${DISTRO_PLUGINS_DIR}/${new_distro_name}.override.sh"
		sed -i "s/^\(DISTRO_NAME=\)\(.*\)\$/\1\"${SUPPORTED_DISTRIBUTIONS["$orig_distro_name"]} - ${new_distro_name}\"/g" "${DISTRO_PLUGINS_DIR}/${new_distro_name}.override.sh"
	else
		msg
		msg "${BRED}Error: could not find a plug-in for distribution '${YELLOW}${orig_distro_name}${BRED}'.${RST}"
		msg
		return 1
	fi

	msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Renaming '${INSTALLED_ROOTFS_DIR}/${orig_distro_name}' to '${INSTALLED_ROOTFS_DIR}/${new_distro_name}'...${RST}"
	mv "${INSTALLED_ROOTFS_DIR}/${orig_distro_name}" "${INSTALLED_ROOTFS_DIR}/${new_distro_name}"

	msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Updating PRoot link2symlink extension files (may take long time)...${RST}"
	local symlink_file_name
	find "${INSTALLED_ROOTFS_DIR}/${new_distro_name}" -type l | while read -r symlink_file_name; do
		local symlink_current_target
		symlink_current_target=$(readlink "$symlink_file_name")
		if [ "${symlink_current_target:0:${#INSTALLED_ROOTFS_DIR}}" != "${INSTALLED_ROOTFS_DIR}" ]; then
			# Skip non-l2s symlinks.
			continue
		fi
		local symlink_new_target
		symlink_new_target=$(sed -E "s@(${INSTALLED_ROOTFS_DIR})/([^/]+)/(.*)@\1/${new_distro_name}/\3@g" <<< "$symlink_current_target")
		ln -sf "$symlink_new_target" "$symlink_file_name"
	done

	msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Finished.${RST}"
}

command_rename_help() {
	msg
	msg "${BYELLOW}Usage: ${BCYAN}${PROGRAM_NAME} ${GREEN}rename ${CYAN}[${GREEN}ORIG ALIAS${CYAN}] [${GREEN}NEW ALIAS${CYAN}]${RST}"
	msg
	msg "${CYAN}Command aliases: ${GREEN}mv${RST}"
	msg
	msg "${CYAN}Rename a specified Linux distribution.${RST}"
	msg
	msg "${CYAN}Note that renaming default distribution will take a while${RST}"
	msg "${CYAN}as PRoot-Distro has to update symlinks. If user renames a${RST}"
	msg "${CYAN}default distribution, the plug-in copy will be created.${RST}"
	msg
	msg "${CYAN}Options:${RST}"
	msg
	msg "  ${GREEN}--help               ${CYAN}- Show this help information.${RST}"
	msg
	msg "${CYAN}Selected distribution should be referenced by alias which can be${RST}"
	msg "${CYAN}obtained by this command: ${GREEN}${PROGRAM_NAME} list${RST}"
	msg
	show_version
	msg
}

#############################################################################
#
# FUNCTION TO REINSTALL THE GIVEN DISTRIBUTION
#
# A wrapper unifying functions command_remove && command_install.
#
#############################################################################

command_reset() {
	local distro_name

	while (($# >= 1)); do
		case "$1" in
			-h|--help)
				command_reset_help
				return 0
				;;
			-*)
				msg
				msg "${BRED}Error: got unknown option '${YELLOW}${1}${BRED}'.${RST}"
				command_reset_help
				return 1
				;;
			*)
				if [ -z "${distro_name-}" ]; then
					if [ -z "$1" ]; then
						msg
						msg "${BRED}Error: distribution alias argument should not be empty.${RST}"
						command_reset_help
						return 1
					fi
					distro_name="$1"
				else
					msg
					msg "${BRED}Error: got excessive positional argument '${YELLOW}${1}${BRED}'. Note that distribution can be specified only once.${RST}"
					command_reset_help
					return 1
				fi
				;;
		esac
		shift 1
	done

	if [ -z "${distro_name-}" ]; then
		msg
		msg "${BRED}Error: distribution alias is not specified.${RST}"
		command_reset_help
		return 1
	fi

	if [ -z "${SUPPORTED_DISTRIBUTIONS["$distro_name"]+x}" ]; then
		msg
		msg "${BRED}Error: unknown distribution '${YELLOW}${distro_name}${BRED}' was requested to be reset.${RST}"
		msg
		msg "${CYAN}View supported distributions by: ${GREEN}${PROGRAM_NAME} list${RST}"
		msg
		return 1
	fi

	if [ ! -d "${INSTALLED_ROOTFS_DIR}/${distro_name}" ]; then
		msg
		msg "${BRED}Error: distribution '${YELLOW}${distro_name}${BRED}' is not installed.${RST}"
		msg
		return 1
	fi

	CMD_REMOVE_REQUESTED_RESET="true" command_remove "$distro_name"
	command_install "$distro_name"
}

command_reset_help() {
	msg
	msg "${BYELLOW}Usage: ${BCYAN}${PROGRAM_NAME} ${GREEN}reset ${CYAN}[${GREEN}DISTRIBUTION ALIAS${CYAN}]${RST}"
	msg
	msg "${CYAN}Reinstall the specified Linux distribution.${RST}"
	msg
	msg "${CYAN}Options:${RST}"
	msg
	msg "  ${GREEN}--help               ${CYAN}- Show this help information.${RST}"
	msg
	msg "${CYAN}Be careful when using it because you will not be prompted for${RST}"
	msg "${CYAN}confirmation and all data saved within the distribution will${RST}"
	msg "${CYAN}instantly gone.${RST}"
	msg
	msg "${CYAN}Selected distribution should be referenced by alias which can be${RST}"
	msg "${CYAN}obtained by this command: ${GREEN}${PROGRAM_NAME} list${RST}"
	msg
	show_version
	msg
}

#############################################################################
#
# FUNCTION TO START SHELL OR EXECUTE COMMAND
#
# Starts root shell inside the rootfs of specified Linux distribution.
#
# If '--' with further arguments was specified, then execute command line
# given after '--' as root user without starting interactive shell.
#
#############################################################################

command_login() {
	local fix_low_ports=false
	local isolated_environment=false
	local use_termux_home=false
	local make_host_tmp_shared=false
	local -a custom_fs_bindings
	local no_link2symlink=false
	local no_sysvipc=false
	local no_kill_on_exit=false
	local no_arch_warning=false
	local login_user="root"
	local login_wd=""
	local -a login_env_vars
	login_env_vars=("PATH=${DEFAULT_PATH_ENV}")
	local kernel_release="${DEFAULT_FAKE_KERNEL_RELEASE}"
	local hostname="localhost"
	local distro_name

	while (($# >= 1)); do
		case "$1" in
			--)
				shift 1
				break
				;;
			--help)
				command_login_help
				return 0
				;;
			--fix-low-ports)
				fix_low_ports=true
				;;
			--isolated)
				isolated_environment=true
				;;
			--termux-home)
				use_termux_home=true
				;;
			--shared-tmp)
				make_host_tmp_shared=true
				;;
			--bind)
				if [ $# -ge 2 ]; then
					shift 1

					if [ -z "$1" ]; then
						msg
						msg "${BRED}Error: argument to option '${YELLOW}--bind${BRED}' should not be empty.${RST}"
						command_login_help
						return 1
					fi

					custom_fs_bindings+=("$1")
				else
					msg
					msg "${BRED}Error: option '${YELLOW}--bind${BRED}' requires an argument.${RST}"
					command_login_help
					return 1
				fi
				;;
			--no-link2symlink)
				no_link2symlink=true
				;;
			--no-sysvipc)
				no_sysvipc=true
				;;
			--no-kill-on-exit)
				no_kill_on_exit=true
				;;
			--no-arch-warning)
				no_arch_warning=true
				;;
			--user)
				if [ $# -ge 2 ]; then
					shift 1

					if [ -z "$1" ]; then
						msg
						msg "${BRED}Error: argument to option '${YELLOW}--user${BRED}' should not be empty.${RST}"
						command_login_help
						return 1
					fi

					login_user="$1"
				else
					msg
					msg "${BRED}Error: option '${YELLOW}--user${BRED}' requires an argument.${RST}"
					command_login_help
					return 1
				fi
				;;
			--kernel)
				if [ $# -ge 2 ]; then
					shift 1

					if [ -z "$1" ]; then
						msg
						msg "${BRED}Error: argument to option '${YELLOW}--kernel${BRED}' should not be empty.${RST}"
						command_login_help
						return 1
					fi

					kernel_release="$1"
				else
					msg
					msg "${BRED}Error: option '${YELLOW}$1${BRED}' requires an argument.${RST}"
					command_login_help
					return 1
				fi
				;;
			--hostname)
				if [ $# -ge 2 ]; then
					shift 1

					if [ -z "$1" ]; then
						msg
						msg "${BRED}Error: argument to option '${YELLOW}--hostname${BRED}' should not be empty.${RST}"
						command_login_help
						return 1
					fi

					hostname="$1"
				else
					msg
					msg "${BRED}Error: option '${YELLOW}$1${BRED}' requires an argument.${RST}"
					command_login_help
					return 1
				fi
				;;
			--work-dir)
				if [ $# -ge 2 ]; then
					shift 1

					if [ -z "$1" ]; then
						msg
						msg "${BRED}Error: argument to option '${YELLOW}--work-dir${BRED}' should not be empty.${RST}"
						command_login_help
						return 1
					fi

					login_wd="$1"
				else
					msg
					msg "${BRED}Error: option '${YELLOW}--work-dir${BRED}' requires an argument.${RST}"
					command_login_help
					return 1
				fi
				;;
			--env)
				if [ $# -ge 2 ]; then
					shift 1

					if [ -z "$1" ]; then
						msg
						msg "${BRED}Error: argument to option '${YELLOW}--env${BRED}' should not be empty.${RST}"
						command_login_help
						return 1
					fi

					login_env_vars+=("$1")
				else
					msg
					msg "${BRED}Error: option '${YELLOW}--env${BRED}' requires an argument.${RST}"
					command_login_help
					return 1
				fi
				;;
			-*)
				msg
				msg "${BRED}Error: got unknown option '${YELLOW}${1}${BRED}'.${RST}"
				command_login_help
				return 1
				;;
			*)
				if [ -z "${distro_name-}" ]; then
					if [ -z "$1" ]; then
						msg
						msg "${BRED}Error: distribution alias argument should not be empty.${RST}"
						command_login_help
						return 1
					fi
					distro_name="$1"
				else
					msg
					msg "${BRED}Error: got excessive positional argument '${YELLOW}${1}${BRED}'. Note that distribution can be specified only once.${RST}"
					command_login_help
					return 1
				fi
				;;
		esac
		shift 1
	done

	if [ -z "${distro_name-}" ]; then
		msg
		msg "${BRED}Error: distribution alias is not specified.${RST}"
		command_login_help
		return 1
	fi

	if [ -z "${SUPPORTED_DISTRIBUTIONS["$distro_name"]+x}" ]; then
		msg
		msg "${BRED}Error: unknown distribution '${YELLOW}${distro_name}${BRED}' was requested for logging in.${RST}"
		msg
		msg "${CYAN}View supported distributions by: ${GREEN}${PROGRAM_NAME} list${RST}"
		msg
		return 1
	fi

	if [ ! -d "${INSTALLED_ROOTFS_DIR}/${distro_name}" ]; then
		msg
		msg "${BRED}Error: distribution '${YELLOW}${distro_name}${BRED}' is not installed.${RST}"
		msg
		return 1
	fi

	local target_arch dist_type
	target_arch=$(detect_cpu_arch "${distro_name}")
	if [ -f "${DISTRO_PLUGINS_DIR}/${distro_name}.sh" ]; then
		# shellcheck disable=SC1090
		[ "$target_arch" = "unknown" ] && target_arch=$(. "${DISTRO_PLUGINS_DIR}/${distro_name}.sh"; echo "${DISTRO_ARCH}")
		dist_type=$(. "${DISTRO_PLUGINS_DIR}/${distro_name}.sh"; echo "${DISTRO_TYPE-normal}")
	elif [ -f "${DISTRO_PLUGINS_DIR}/${distro_name}.override.sh" ]; then
		# shellcheck disable=SC1090
		[ "$target_arch" = "unknown" ] && target_arch=$(. "${DISTRO_PLUGINS_DIR}/${distro_name}.override.sh"; echo "${DISTRO_ARCH}")
		dist_type=$(. "${DISTRO_PLUGINS_DIR}/${distro_name}.override.sh"; echo "${DISTRO_TYPE-normal}")
	else
		# This should never happen.
		msg
		msg "${BRED}Error: missing plugin for distribution '${YELLOW}${distro_name}${BRED}'.${RST}"
		msg
		return 1
	fi

	# Initialize proot command line arguments array.
	if [ $# -ge 1 ]; then
		# Escape each argument to prevent word splitting.
		set -- "-c" "$(printf " %q" "$@")"
	else
		set --
	fi

	local login_home login_shell
	if [ "${dist_type-normal}" = "termux" ]; then
		if [ -z "${login_wd}" ]; then
			login_wd="/data/data/com.termux/files/home"
		fi
		login_shell="/data/data/com.termux/files/usr/bin/login"
		set -- "/data/data/com.termux/files/usr/bin/env" \
			"HOME=/data/data/com.termux/files/home" \
			"PATH=/data/data/com.termux/files/usr/bin" \
			"PREFIX=/data/data/com.termux/files/usr" \
			"TMPDIR=/data/data/com.termux/files/usr/tmp" \
			"${login_shell}" \
			"$@"
	else
		if [ -d "${INSTALLED_ROOTFS_DIR}/${distro_name}/.l2s" ]; then
			export PROOT_L2S_DIR="${INSTALLED_ROOTFS_DIR}/${distro_name}/.l2s"
		fi

		# It's hard to work without /etc/passwd.
		if [ ! -e "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/passwd" ]; then
			msg "${BRED}Error: the selected distribution doesn't have /etc/passwd.${RST}"
			return 1
		fi

		# Catch invalid specified user before login command will be executed.
		if ! grep -q "${login_user}:" "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/passwd" >/dev/null 2>&1; then
			msg "${BRED}Error: no user '${YELLOW}${login_user}${BRED}' defined in /etc/passwd of distribution.${RST}"
			return 1
		fi

		local login_uid login_gid
		login_uid=$(grep "^${login_user}:" "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/passwd" | cut -d ':' -f 3)
		if [ -z "${login_uid}" ]; then
			msg "${BRED}Error: failed to retrieve the id of user '${YELLOW}${login_user}${BRED}' from /etc/passwd of distribution.${RST}"
			return 1
		fi
		login_gid=$(grep "^${login_user}:" "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/passwd" | cut -d ':' -f 4)
		if [ -z "${login_gid}" ]; then
			msg "${BRED}Error: failed to retrieve the primary group id of user '${YELLOW}${login_user}${BRED}' from /etc/passwd of distribution.${RST}"
			return 1
		fi
		login_home=$(grep "^${login_user}:" "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/passwd" | cut -d ':' -f 6)
		if [ -z "${login_home}" ]; then
			msg "${BRED}Error: failed to retrieve the home of user '${YELLOW}${login_user}${BRED}' from /etc/passwd of distribution.${RST}"
			return 1
		fi
		if [ -z "${login_wd}" ]; then
			login_wd="${login_home}"
		fi
		#if [ ! -d "$(realpath "${INSTALLED_ROOTFS_DIR}/${distro_name}/${login_wd}")" ]; then
		#	msg "${BRED}Warning: cannot use path '${YELLOW}${login_wd}${BRED}' as working directory.${RST}"
		#fi
		login_shell=$(grep "^${login_user}:" "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/passwd" | cut -d ':' -f 7)
		if [ -z "${login_shell}" ]; then
			msg "${BRED}Error: failed to retrieve the shell of user '${YELLOW}${login_user}${BRED}' from /etc/passwd of distribution.${RST}"
			return 1
		fi

		# Update Android-specific variables in /etc/environment.
		# Needed to handle changes after Android OS was upgraded.
		chmod u+rw "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/environment" >/dev/null 2>&1 || true
		for var in ANDROID_ART_ROOT ANDROID_DATA ANDROID_I18N_ROOT ANDROID_ROOT \
			ANDROID_RUNTIME_ROOT ANDROID_TZDATA_ROOT BOOTCLASSPATH \
			DEX2OATBOOTCLASSPATH; do
			set +u
			if [ -n "${!var}" ]; then
				# Create new variable entry instead of editing as variable may
				# not exist in the file.
				sed -i "/^${var}=/d" "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/environment"
				echo "${var}=${!var}" >> "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/environment"
			fi
			set -u
		done
		unset var

		for var in ANDROID_ART_ROOT ANDROID_DATA ANDROID_I18N_ROOT ANDROID_ROOT \
			ANDROID_RUNTIME_ROOT ANDROID_TZDATA_ROOT BOOTCLASSPATH \
			DEX2OATBOOTCLASSPATH EXTERNAL_STORAGE; do
			set +u
			if [ -n "${!var}" ]; then
				login_env_vars+=("${var}=${!var}")
			fi
			set -u
		done
		unset var

		# Handle /etc/environment.
		if [ -e "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/environment" ]; then
			mapfile -t -O "${#login_env_vars[@]}" login_env_vars < <(
				grep -P '^[A-Za-z_][A-Za-z0-9_]+=.+' "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/environment" | \
					sed -E \
						-e "s/^([^=]+=)['\"]/\1/g" \
						-e "s/['\"]\$//g" \
						-e "/^[^=]+\$/d"
			)
		fi

		# Using '-i' to ensure that we can fully control which
		# environment variables will be inherited by shell.
		set -- "/usr/bin/env" "-i" \
			"${login_env_vars[@]}" \
			"COLORTERM=${COLORTERM-}" \
			"HOME=${login_home}" \
			"USER=${login_user}" \
			"TERM=${TERM-xterm-256color}" \
			"${login_shell}" \
			"-l" \
			"$@"

		set -- "--change-id=${login_uid}:${login_gid}" "$@"
	fi

	set -- "--rootfs=${INSTALLED_ROOTFS_DIR}/${distro_name}" "$@"
	set -- "--cwd=${login_wd}" "$@"

	local need_cpu_emulator=false
	if [ "$target_arch" != "$DEVICE_CPU_ARCH" ]; then
		local cpu_emulator_path=""
		need_cpu_emulator=true

		# If CPU and host OS are 64bit, we can run 32bit guest OS without emulation.
		# Everything else requires emulator (QEMU).
		case "$target_arch" in
			aarch64) cpu_emulator_path="@TERMUX_PREFIX@/bin/qemu-aarch64";;
			arm)
				if [ "$DEVICE_CPU_ARCH" != "aarch64" ] || ! $SUPPORT_32BIT; then
					cpu_emulator_path="@TERMUX_PREFIX@/bin/qemu-arm"
				else
					need_cpu_emulator=false
				fi
				;;
			i686)
				if [ "$DEVICE_CPU_ARCH" != "x86_64" ]; then
					cpu_emulator_path="@TERMUX_PREFIX@/bin/qemu-i386"
				else
					need_cpu_emulator=false
				fi
				;;
			riscv64) cpu_emulator_path="@TERMUX_PREFIX@/bin/qemu-riscv64";;
			x86_64)
				if [ "$PROOT_DISTRO_X64_EMULATOR" = "QEMU" ]; then
					cpu_emulator_path="@TERMUX_PREFIX@/bin/qemu-x86_64"
				elif [ "$PROOT_DISTRO_X64_EMULATOR" = "BLINK" ]; then
					cpu_emulator_path="@TERMUX_PREFIX@/bin/blink"
				else
					msg
					msg "${BRED}Error: PROOT_DISTRO_X64_EMULATOR has unknown value '${YELLOW}${PROOT_DISTRO_X64_EMULATOR}${BRED}'. Valid values are: BLINK, QEMU."
					msg
				fi
				;;
			*)
				msg
				msg "${BRED}Error: DISTRO_ARCH has unknown value '${YELLOW}${target_arch}${BRED}'. Valid values are: aarch64, arm, i686, riscv64, x86_64."
				msg
				return 1
			;;
		esac

		if [ -n "$cpu_emulator_path" ]; then
			if [ -x "$cpu_emulator_path" ]; then
				set -- "-q" "$cpu_emulator_path" "$@"
			else
				local cpu_emulator_pkg=""
				case "$target_arch" in
					aarch64) cpu_emulator_pkg="qemu-user-aarch64";;
					arm) cpu_emulator_pkg="qemu-user-arm";;
					i686) cpu_emulator_pkg="qemu-user-i386";;
					riscv64) cpu_emulator_pkg="qemu-user-riscv64";;
					x86_64)
						if [ "$PROOT_DISTRO_X64_EMULATOR" = "QEMU" ]; then
							cpu_emulator_pkg="qemu-user-x86-64"
						elif [ "$PROOT_DISTRO_X64_EMULATOR" = "BLINK" ]; then
							cpu_emulator_pkg="blink"
						else
							msg
							msg "${BRED}Error: PROOT_DISTRO_X64_EMULATOR has unknown value '${YELLOW}${PROOT_DISTRO_X64_EMULATOR}${BRED}'. Valid values are: BLINK, QEMU."
							msg
						fi
						;;
					*) cpu_emulator_pkg="qemu-user-$target_arch";;
				esac

				msg
				msg "${BRED}Error: package '${YELLOW}${cpu_emulator_pkg}${BRED}' is not installed.${RST}"
				msg
				return 1
			fi
		fi
	else
		# Warn about CPU not supporting 32-bit instructions
		if ! $no_arch_warning && ! $SUPPORT_32BIT; then
			msg "${BRED}Warning: CPU doesn't support 32-bit instructions, some software may not work.${RST}"
		fi
	fi

	if ! $no_kill_on_exit; then
		# This option terminates all background processes on exit, so
		# proot can terminate freely.
		set -- "--kill-on-exit" "$@"
	else
		msg "${BRED}Warning: option '${YELLOW}--no-kill-on-exit${BRED}' is enabled. When exiting, your session will be blocked until all processes are terminated.${RST}"
	fi

	if [ "${dist_type-normal}" != "termux" ] && ! $no_link2symlink; then
		# Support hardlinks.
		set -- "--link2symlink" "$@"
	fi

	if ! $no_sysvipc; then
		# Support System V IPC.
		set -- "--sysvipc" "$@"
	fi

	# Some devices have old kernels and GNU libc refuses to work on them.
	# Fix this behavior by reporting a fake up-to-date kernel version.
	set -- "--kernel-release=\\Linux\\${hostname}\\${kernel_release}\\${DEFAULT_FAKE_KERNEL_VERSION}\\$(uname -m)\\localdomain\\-1\\" "$@"

	# Fix lstat to prevent dpkg symlink size warnings
	set -- "-L" "$@"

	# Core file systems that should always be present.
	set -- "--bind=/dev" "$@"
	set -- "--bind=/proc" "$@"
	set -- "--bind=/sys" "$@"

	if [ "${dist_type-normal}" != "termux" ]; then
		set -- "--bind=/dev/urandom:/dev/random" "$@"
		set -- "--bind=/proc/self/fd:/dev/fd" "$@"

		# Bind /proc/self/fd/{0,1,2} only if not launched under pipe
		local i fds
		fds=(stdin stdout stderr)
		for i in "${!fds[@]}"; do
			realpath -qe "/proc/self/fd/$i" >/dev/null && set -- "--bind=/proc/self/fd/$i:/dev/${fds[i]}" "$@"
		done
		unset i fds

		# Ensure that we can bind fake /proc and /sys entries.
		setup_fake_sysdata

		# With this tools should assume that no SELinux present.
		set -- "--bind=${INSTALLED_ROOTFS_DIR}/${distro_name}/sys/.empty:/sys/fs/selinux" "$@"

		# Fake various /proc entries commonly used by programs unless read access
		# available.
		if ! cat /proc/loadavg > /dev/null 2>&1; then
			set -- "--bind=${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.loadavg:/proc/loadavg" "$@"
		fi
		if ! cat /proc/stat > /dev/null 2>&1; then
			set -- "--bind=${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.stat:/proc/stat" "$@"
		fi
		if ! cat /proc/uptime > /dev/null 2>&1; then
			set -- "--bind=${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.uptime:/proc/uptime" "$@"
		fi
		if ! cat /proc/version > /dev/null 2>&1; then
			set -- "--bind=${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.version:/proc/version" "$@"
		fi
		if ! cat /proc/vmstat > /dev/null 2>&1; then
			set -- "--bind=${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.vmstat:/proc/vmstat" "$@"
		fi
		if ! cat /proc/sys/kernel/cap_last_cap > /dev/null 2>&1; then
			set -- "--bind=${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.sysctl_entry_cap_last_cap:/proc/sys/kernel/cap_last_cap" "$@"
		fi
		if ! cat /proc/sys/fs/inotify/max_user_watches > /dev/null 2>&1; then
			set -- "--bind=${INSTALLED_ROOTFS_DIR}/${distro_name}/proc/.sysctl_inotify_max_user_watches:/proc/sys/fs/inotify/max_user_watches" "$@"
		fi

		# Bind /tmp to /dev/shm.
		if [ ! -d "${INSTALLED_ROOTFS_DIR}/${distro_name}/tmp" ]; then
			mkdir -p "${INSTALLED_ROOTFS_DIR}/${distro_name}/tmp"
			chmod 1777 "${INSTALLED_ROOTFS_DIR}/${distro_name}/tmp"
		fi
		set -- "--bind=${INSTALLED_ROOTFS_DIR}/${distro_name}/tmp:/dev/shm" "$@"
	fi

	# When running in non-isolated mode, provide some bindings specific
	# to Android and Termux so user can interact with host file system.
	if ! $isolated_environment; then
		for data_dir in /data/app /data/dalvik-cache \
			/data/misc/apexdata/com.android.art/dalvik-cache; do
			[ ! -d "$data_dir" ] && continue
			local dir_mode
			dir_mode=$(stat --format='%a' "$data_dir")
			if [[ ${dir_mode:2} =~ ^[157]$ ]]; then
				set -- "--bind=${data_dir}" "$@"
			fi
		done
		unset data_dir

		if [ -d "/data/data/@TERMUX_APP_PACKAGE@/files/apps" ]; then
			set -- "--bind=/data/data/@TERMUX_APP_PACKAGE@/files/apps" "$@"
		fi

		# These bindings not available by default when running Termux distro.
		if [ "${dist_type-normal}" != "termux" ]; then
			set -- "--bind=/data/data/@TERMUX_APP_PACKAGE@/cache" "$@"
			set -- "--bind=@TERMUX_HOME@" "$@"
		else
			# For package manager in 'termux' distribution.
			mkdir -p "${INSTALLED_ROOTFS_DIR}/${distro_name}/data/data/com.termux/cache"
		fi

		# Bind whole /storage directory when it is readable. This gives
		# access to shared storage and on some Android versions to external
		# disks such as SD cards. On failure try binding only shared
		# storage.
		if ls -1U /storage > /dev/null 2>&1; then
			set -- "--bind=/storage" "$@"
			set -- "--bind=/storage/emulated/0:/sdcard" "$@"
		else
			# We want to use the primary shared storage mount point
			# there with avoiding secondary and legacy mount points. As
			# Android OS versions are different, some directories may
			#be unavailable and we need to try them all.
			local storage_path
			if ls -1U /storage/self/primary/ > /dev/null 2>&1; then
				storage_path="/storage/self/primary"
			elif ls -1U /storage/emulated/0/ > /dev/null 2>&1; then
				storage_path="/storage/emulated/0"
			elif ls -1U /sdcard/ > /dev/null 2>&1; then
				storage_path="/sdcard"
			else
				# Shared storage is not accessible.
				storage_path=""
			fi

			if [ -n "$storage_path" ]; then
				set -- "--bind=${storage_path}:/sdcard" "$@"
				set -- "--bind=${storage_path}:/storage/emulated/0" "$@"
				set -- "--bind=${storage_path}:/storage/self/primary" "$@"
			fi
		fi
	fi

	# When using QEMU, we need some host files even in isolated mode.
	# Force enabled for Termux distribution.
	if ! $isolated_environment || [ "${dist_type-normal}" = "termux" ] || $need_cpu_emulator; then
		local system_mnt
		for system_mnt in /apex /odm /product /system /system_ext /vendor \
			/linkerconfig/ld.config.txt \
			/linkerconfig/com.android.art/ld.config.txt \
			/plat_property_contexts /property_contexts; do

			if [ -e "$system_mnt" ]; then
				system_mnt=$(realpath "$system_mnt")
			else
				continue
			fi

			if [ -d "$system_mnt" ]; then
				local dir_mode
				dir_mode=$(stat --format='%a' "$system_mnt")
				if [[ ${dir_mode:2} =~ ^[157]$ ]]; then
					set -- "--bind=${system_mnt}" "$@"
				fi
			elif [ -f "$system_mnt" ]; then
				if head -c 1 "$system_mnt" >/dev/null 2>&1; then
					set -- "--bind=${system_mnt}" "$@"
				fi
			else
				continue
			fi
		done

		# Termux prefix can be bound only for non-Termux distributions.
		if [ "${dist_type-normal}" != "termux" ]; then
			set -- "--bind=@TERMUX_PREFIX@" "$@"
		fi
	fi

	# Use Termux home directory if requested.
	# Ignores --isolated.
	if $use_termux_home; then
		if [ "${dist_type-normal}" = "termux" ]; then
			set -- "--bind=@TERMUX_HOME@:/data/data/com.termux/files/home" "$@"
		else
			if [ "$login_user" = "root" ]; then
				set -- "--bind=@TERMUX_HOME@:/root" "$@"
			else
				if [ -f "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/passwd" ]; then
					local user_home
					user_home=$(grep -P "^${login_user}:" "${INSTALLED_ROOTFS_DIR}/${distro_name}/etc/passwd" | cut -d: -f 6)

					if [ -z "$user_home" ]; then
						user_home="/home/${login_user}"
					fi

					set -- "--bind=@TERMUX_HOME@:${user_home}" "$@"
				else
					set -- "--bind=@TERMUX_HOME@:/home/${login_user}" "$@"
				fi
			fi
		fi
	fi

	# Bind the tmp folder from the host system to the guest system
	# Ignores --isolated.
	if $make_host_tmp_shared; then
		set -- "--bind=@TERMUX_PREFIX@/tmp:/tmp" "$@"
	fi

	# Bind custom file systems.
	local bnd
	for bnd in "${custom_fs_bindings[@]}"; do
		set -- "--bind=${bnd}" "$@"
	done

	# Modify bindings to protected ports to use a higher port number.
	if $fix_low_ports; then
		set -- "-p" "$@"
	fi

	# Prevent possible conflicts with proot.
	unset LD_PRELOAD

	exec proot "$@"
}

command_login_help() {
	msg
	msg "${BYELLOW}Usage: ${BCYAN}${PROGRAM_NAME} ${GREEN}login ${CYAN}[${GREEN}OPTIONS${CYAN}] [${GREEN}DISTRO ALIAS${CYAN}] [${GREEN}-- ${CYAN}[${GREEN}COMMAND${CYAN}]]${RST}"
	msg
	msg "${CYAN}Command aliases: ${GREEN}sh${RST}"
	msg
	msg "${CYAN}Launch a login shell for the specified distribution if no${RST}"
	msg "${CYAN}additional arguments were given. Otherwise execute the${RST}"
	msg "${CYAN}given command and exit.${RST}"
	msg
	msg "${CYAN}Options:${RST}"
	msg
	msg "  ${GREEN}--help               ${CYAN}- Show this help information.${RST}"
	msg
	msg "  ${GREEN}--user [user]        ${CYAN}- Login as specified user instead of 'root'.${RST}"
	msg "                         ${CYAN}Not applicable for distribution 'termux'.${RST}"
	msg
	msg "  ${GREEN}--fix-low-ports      ${CYAN}- Modify bindings to protected ports to use${RST}"
	msg "                         ${CYAN}a higher port number.${RST}"
	msg
	msg "  ${GREEN}--isolated           ${CYAN}- Run isolated environment without access${RST}"
	msg "                         ${CYAN}to host file system.${RST}"
	msg
	msg "  ${GREEN}--termux-home        ${CYAN}- Mount Termux home directory to /root.${RST}"
	msg "                         ${CYAN}Takes priority over '${GREEN}--isolated${CYAN}' option.${RST}"
	msg
	msg "  ${GREEN}--shared-tmp         ${CYAN}- Mount Termux temp directory to /tmp.${RST}"
	msg "                         ${CYAN}Takes priority over '${GREEN}--isolated${CYAN}' option.${RST}"
	msg
	msg "  ${GREEN}--bind [path:path]   ${CYAN}- Custom file system binding. Can be specified${RST}"
	msg "                         ${CYAN}multiple times.${RST}"
	msg "                         ${CYAN}Takes priority over '${GREEN}--isolated${CYAN}' option.${RST}"
	msg
	msg "  ${GREEN}--no-link2symlink    ${CYAN}- Disable hardlink emulation by proot.${RST}"
	msg "                         ${CYAN}Adviseable only on devices with SELinux${RST}"
	msg "                         ${CYAN}in permissive mode. Not applicable for${RST}"
	msg "                         ${CYAN}distribution 'termux'.${RST}"
	msg
	msg "  ${GREEN}--no-sysvipc         ${CYAN}- Disable System V IPC emulation by proot.${RST}"
	msg
	msg "  ${GREEN}--no-kill-on-exit    ${CYAN}- Wait until all running processes will finish${RST}"
	msg "                         ${CYAN}before exiting. This will cause proot to${RST}"
	msg "                         ${CYAN}freeze if you are running daemons.${RST}"
	msg
	msg "  ${GREEN}--no-arch-warning    ${CYAN}- Suppress warning about CPU not supporting 32-bit${RST}"
	msg "                         ${CYAN}instructions.${RST}"
	msg
	msg "  ${GREEN}--kernel [string]    ${CYAN}- Customize Linux kernel release string shown by${RST}"
	msg "                         ${CYAN}uname command.${RST}"
	msg
	msg "  ${GREEN}--hostname [string]  ${CYAN}- Customize system host name.${RST}"
	msg
	msg "  ${GREEN}--work-dir [path]    ${CYAN}- Set the working directory.${RST}"
	msg
	msg "  ${GREEN}--env ENV=val        ${CYAN}- Set environment variable. Can be specified${RST}"
	msg "                         ${CYAN}multiple times.${RST}"
	msg
	msg "${CYAN}Put '${GREEN}--${CYAN}' if you wish to stop command line processing and pass${RST}"
	msg "${CYAN}options as shell arguments.${RST}"
	msg
	msg "${CYAN}If no '${GREEN}--isolated${CYAN}' option given, the following host directories${RST}"
	msg "${CYAN}will be available:${RST}"
	msg
	msg "  ${CYAN}* ${YELLOW}/apex ${CYAN}(only Android 10+)${RST}"
	msg "  ${CYAN}* ${YELLOW}/data/dalvik-cache${RST}"
	msg "  ${CYAN}* ${YELLOW}/data/data/@TERMUX_APP_PACKAGE@${RST}"
	msg "  ${CYAN}* ${YELLOW}/sdcard${RST}"
	msg "  ${CYAN}* ${YELLOW}/storage${RST}"
	msg "  ${CYAN}* ${YELLOW}/system${RST}"
	msg "  ${CYAN}* ${YELLOW}/vendor${RST}"
	msg
	msg "${CYAN}This should be enough to get Termux utilities like termux-api or${RST}"
	msg "${CYAN}termux-open get working. If they do not work for some reason,${RST}"
	msg "${CYAN}make sure they are properly set in ${YELLOW}/etc/environment${CYAN}.${RST}"
	msg "${CYAN}Also check whether they define variables like ANDROID_DATA,${RST}"
	msg "${CYAN}ANDROID_ROOT, BOOTCLASSPATH and others which are usually set${RST}"
	msg "${CYAN}in Termux sessions.${RST}"
	msg
	msg "${CYAN}If issue occurs only after su/sudo use, then likely your PAM${RST}"
	msg "${CYAN}configuration doesn't load ${YELLOW}/etc/environment${CYAN} and you need to fix${RST}"
	msg "${CYAN}it by enabling pam_env.so in /etc/pam.d configuration.${RST}"
	msg
	msg "${CYAN}Example PAM configuration line:${RST}"
	msg
	msg "  ${GREEN}session  required  pam_env.so readenv=1${RST}"
	msg
	msg "${CYAN}You need to append it to ${YELLOW}/etc/pam.d/su${CYAN}, ${YELLOW}/etc/pam.d/sudo${CYAN} or other${RST}"
	msg "${CYAN}file depending on distribution.${RST}"
	msg
	msg "${CYAN}When using distribution 'termux' some of mentioned directories${RST}"
	msg "${CYAN}such as /system are always mounted to satisfy requirements.${RST}"
	msg
	msg "${CYAN}Selected distribution should be referenced by alias which can be${RST}"
	msg "${CYAN}obtained by this command: ${GREEN}${PROGRAM_NAME} list${RST}"
	msg
	show_version
	msg
}

#############################################################################
#
# FUNCTION TO LIST THE SUPPORTED DISTRIBUTIONS
#
# Print the summary of available distributions and their installation
# status. The information about distributions is read from plug-in files.
#
#############################################################################

command_list() {
	local verbose=false

	while (($# >= 1)); do
		case "$1" in
			-h|--help)
				command_list_help
				return 0
				;;
			-v|--verbose)
				verbose=true
				;;
			-*)
				msg
				msg "${BRED}Error: got unknown option '${YELLOW}${1}${BRED}'.${RST}"
				command_list_help
				return 1
				;;
			*)
				msg
				msg "${BRED}Error: got excessive positional argument '${YELLOW}${1}${BRED}'.${RST}"
				command_list_help
				return 1
				;;
		esac
		shift 1
	done

	msg
	if [ -z "${!SUPPORTED_DISTRIBUTIONS[*]}" ]; then
		msg "${YELLOW}No distribution plug-ins found.${RST}"
		msg
		msg "${YELLOW}Please check the directory '${DISTRO_PLUGINS_DIR}' and create at least one distribution plug-in.${RST}"
	else
		if $verbose; then
			msg "${CYAN}Supported distributions:${RST}"
		else
			msg "${CYAN}Supported distributions (format: name < alias >):${RST}"
			msg
		fi

		local i
		for i in $(echo "${!SUPPORTED_DISTRIBUTIONS[@]}" | tr ' ' '\n' | sort -d); do
			if $verbose; then
				msg
				msg "  ${CYAN}* ${YELLOW}${SUPPORTED_DISTRIBUTIONS[$i]}${RST}"
				msg
				msg "    ${CYAN}Alias: ${GREEN}${i}${RST}"
				if [ -d "${INSTALLED_ROOTFS_DIR}/${i}" ]; then
					msg "    ${CYAN}Installed: ${GREEN}yes${RST}"
				else
					msg "    ${CYAN}Installed: ${RED}no${RST}"
				fi
				if [ -n "${SUPPORTED_DISTRIBUTIONS_COMMENTS["${i}"]+x}" ]; then
					msg "    ${CYAN}Comment: ${SUPPORTED_DISTRIBUTIONS_COMMENTS["${i}"]}${RST}"
				fi

				local supported_cpus
				if [ -f "${DISTRO_PLUGINS_DIR}/${i}.sh" ]; then
					supported_cpus=$(source "${DISTRO_PLUGINS_DIR}/${i}.sh"; echo "${!TARBALL_URL[@]}")
				elif [ -f "${DISTRO_PLUGINS_DIR}/${i}.override.sh" ]; then
					supported_cpus=$(source "${DISTRO_PLUGINS_DIR}/${i}.override.sh"; echo "${!TARBALL_URL[@]}")
				else
					supported_cpus="no data"
				fi

				msg "    ${CYAN}Architectures: ${supported_cpus// /, }${RST}"
			else
				msg "  ${CYAN}* ${YELLOW}${SUPPORTED_DISTRIBUTIONS[$i]} ${GREEN}< $i >${RST}"
			fi
		done

		msg
		msg "${CYAN}Install selected one with: ${GREEN}${PROGRAM_NAME} install <alias>${RST}"
	fi
	msg
}

command_list_help() {
	msg
	msg "${BYELLOW}Usage: ${BCYAN}${PROGRAM_NAME} ${GREEN}list${RST}"
	msg
	msg "${CYAN}Command aliases: ${GREEN}ls${RST}"
	msg
	msg "${CYAN}List distributions and their properties.${RST}"
	msg
	msg "${CYAN}Options:${RST}"
	msg
	msg "  ${GREEN}--help               ${CYAN}- Show this help information.${RST}"
	msg
	msg "  ${GREEN}--verbose            ${CYAN}- Detailed output.${RST}"
	msg
	show_version
	msg
}

#############################################################################
#
# FUNCTION TO BACKUP A SPECIFIED DISTRIBUTION
#
# Backup a specified distribution installation by making a tarball that
# contains distribution rootfs and a corresponding plug-in file.
#
#############################################################################

command_backup() {
	local distro_name
	local tarball_file_path

	while (($# >= 1)); do
		case "$1" in
			-h|--help)
				command_backup_help
				return 0
				;;
			--output)
				if [ $# -ge 2 ]; then
					shift 1

					if [ -z "$1" ]; then
						msg
						msg "${BRED}Error: argument to option '${YELLOW}--output${BRED}' should not be empty.${RST}"
						command_backup_help
						return 1
					fi

					tarball_file_path="$1"
				else
					msg
					msg "${BRED}Error: option '${YELLOW}--output${BRED}' requires an argument.${RST}"
					command_backup_help
					return 1
				fi
				;;
			-*)
				msg
				msg "${BRED}Error: got unknown option '${YELLOW}${1}${BRED}'.${RST}"
				command_backup_help
				return 1
				;;
			*)
				if [ -z "${distro_name-}" ]; then
					if [ -z "$1" ]; then
						msg
						msg "${BRED}Error: distribution alias argument should not be empty.${RST}"
						command_backup_help
						return 1
					fi
					distro_name="$1"
				else
					msg
					msg "${BRED}Error: got excessive positional argument '${YELLOW}${1}${BRED}'. Note that distribution can be specified only once.${RST}"
					command_backup_help
					return 1
				fi
				;;
		esac
		shift 1
	done

	if [ -z "${distro_name-}" ]; then
		msg
		msg "${BRED}Error: distribution alias is not specified.${RST}"
		command_backup_help
		return 1
	fi

	if [ -z "${SUPPORTED_DISTRIBUTIONS["$distro_name"]+x}" ]; then
		msg
		msg "${BRED}Error: unknown distribution '${YELLOW}${distro_name}${BRED}' was requested for backup.${RST}"
		msg
		msg "${CYAN}View supported distributions by: ${GREEN}${PROGRAM_NAME} list${RST}"
		msg
		return 1
	fi

	if [ ! -d "${INSTALLED_ROOTFS_DIR}/${distro_name}" ]; then
		msg
		msg "${BRED}Error: distribution '${YELLOW}${distro_name}${BRED}' is not installed.${RST}"
		msg
		return 1
	fi

	# Notify user if tar available in PATH is not GNU tar.
	if ! grep -q 'tar (GNU tar)' <(tar --version 2>/dev/null | head -n 1); then
		msg
		msg "${BRED}Warning: tar binary that is available in PATH appears to be not a GNU tar. You may experience issues during installation, backup and restore operations.${RST}"
		msg
	fi

	msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Backing up ${YELLOW}${SUPPORTED_DISTRIBUTIONS["$distro_name"]}${CYAN}...${RST}"

	if [ -z "${tarball_file_path-}" ]; then
		msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Tarball will be written to stdout.${RST}"

		if [ -t 1 ]; then
			msg
			msg "${BRED}Error: tarball cannot be printed to console. Please use option '${YELLOW}--output${BRED}' to specify a file or use pipe for sending the output to another program.${RST}"
			msg
			return 1
		fi
	else
		msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Tarball will be written to '${tarball_file_path}'.${RST}"

		if [ -d "$tarball_file_path" ]; then
			msg
			msg "${BRED}Error: cannot write to '${YELLOW}${tarball_file_path}${YELLOW}' because this path is a directory.${RST}"
			command_backup_help
			return 1
		fi

		if [ -f "$tarball_file_path" ]; then
			msg
			msg "${BRED}Error: file '${YELLOW}${tarball_file_path}${YELLOW}' already exists. Please specify a different name.${RST}"
			command_backup_help
			return 1
		fi
	fi

	msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Fixing file permissions in rootfs...${RST}"
	# Ensure we can read all files.
	find "${INSTALLED_ROOTFS_DIR}/${distro_name}" -type d -print0 | xargs -0 -r chmod u+rx
	find "${INSTALLED_ROOTFS_DIR}/${distro_name}" -type f -executable -print0 | xargs -0 -r chmod u+rx
	find "${INSTALLED_ROOTFS_DIR}/${distro_name}" -type f ! -executable -print0 | xargs -0 -r chmod u+r

	local distro_plugin_script="${distro_name}.sh"
	if [ ! -f "${DISTRO_PLUGINS_DIR}/${distro_plugin_script}" ]; then
		# Alt name.
		distro_plugin_script="${distro_name}.override.sh"

		# We already passed check for supported distributions but doing
		# this check anyway. Above step with fixing permissions takes enough
		# time to let significant changes on file system happen.
		if [ ! -f "${DISTRO_PLUGINS_DIR}/${distro_plugin_script}" ]; then
			msg
			msg "${BRED}Error: neither '${distro_name}.sh' nor '${distro_name}.override.sh' are available in directory '${DISTRO_PLUGINS_DIR}'.${RST}"
			msg
			return 1
		fi
	fi

	msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Archiving the rootfs and plug-in...${RST}"
	if [ -n "${tarball_file_path-}" ]; then
		# shellcheck disable=SC2064 # variables must expand here
		trap "echo -e \"\\r\\e[2K${BLUE}[${RED}!${BLUE}] ${CYAN}Exiting due to failure.${RST}\"; rm -f \"${tarball_file_path:?}\"; exit 1;" EXIT
		# shellcheck disable=SC2064 # variables must expand here
		trap "trap - EXIT; echo -e \"\\r\\e[2K${BLUE}[${RED}!${BLUE}] ${CYAN}Exiting immediately as requested.${RST}\"; rm -f \"${tarball_file_path:?}\"; exit 1;" HUP INT TERM
		tar -c --auto-compress \
			--warning=no-file-ignored \
			-f "$tarball_file_path" \
			-C "${DISTRO_PLUGINS_DIR}/../" "$(basename "$DISTRO_PLUGINS_DIR")/${distro_plugin_script}" \
			-C "${INSTALLED_ROOTFS_DIR}/../" "$(basename "$INSTALLED_ROOTFS_DIR")/${distro_name}"
		trap - EXIT
		trap 'echo -e "\\r\\e[2K${BLUE}[${RED}!${BLUE}] ${CYAN}Exiting immediately as requested.${RST}"; exit 1;' HUP INT TERM
	else
		tar -c \
			--warning=no-file-ignored \
			-C "${DISTRO_PLUGINS_DIR}/../" "$(basename "$DISTRO_PLUGINS_DIR")/${distro_plugin_script}" \
			-C "${INSTALLED_ROOTFS_DIR}/../" "$(basename "$INSTALLED_ROOTFS_DIR")/${distro_name}"
	fi
	msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Finished.${RST}"
}

command_backup_help() {
	msg
	msg "${BYELLOW}Usage: ${BCYAN}${PROGRAM_NAME} ${GREEN}backup ${CYAN}[${GREEN}DISTRIBUTION ALIAS${CYAN}]${RST}"
	msg
	msg "${CYAN}Command aliases: ${GREEN}bak${CYAN}, ${GREEN}bkp${RST}"
	msg
	msg "${CYAN}Back up a specified distribution installation into tarball.${RST}"
	msg
	msg "${CYAN}Options:${RST}"
	msg
	msg "  ${GREEN}--help               ${CYAN}- Show this help information.${RST}"
	msg
	msg "  ${GREEN}--output [path]      ${CYAN}- Write tarball to specified file.${RST}"
	msg "                         ${CYAN}If not specified, the tarball will be${RST}"
	msg "                         ${CYAN}printed to stdout. File extension affects${RST}"
	msg "                         ${CYAN}used compression (e.g. gz, bz2, xz).${RST}"
	msg "                         ${CYAN}Backup sent to stdout is not compressed.${RST}"
	msg
	msg "${CYAN}Selected distribution should be referenced by alias which can be${RST}"
	msg "${CYAN}obtained by this command: ${GREEN}${PROGRAM_NAME} list${RST}"
	msg
	show_version
	msg
}

#############################################################################
#
# FUNCTION TO RESTORE A SPECIFIED DISTRIBUTION
#
# Restore a specified distribution installation from the backup (tarball).
# The supplied tarball should be one made by PRoot-Distro as it has a proper
# structure. Regular rootfs tarball will not work here.
#
#############################################################################

command_restore() {
	local tarball_file_path

	while (($# >= 1)); do
		case "$1" in
			-h|--help)
				command_restore_help
				return 0
				;;
			-*)
				msg
				msg "${BRED}Error: got unknown option '${YELLOW}${1}${BRED}'.${RST}"
				command_restore_help
				return 1
				;;
			*)
				if [ -z "${tarball_file_path-}" ]; then
					if [ -z "$1" ]; then
						msg
						msg "${BRED}Error: tarball file path argument should not be empty.${RST}"
						command_restore_help
						return 1
					fi
					tarball_file_path="$1"
				else
					msg
					msg "${BRED}Error: got excessive positional argument '${YELLOW}${1}${BRED}'. Note that tarball file path can be specified only once.${RST}"
					command_restore_help
					return 1
				fi
				;;
		esac
		shift 1
	done

	if [ -n "${tarball_file_path-}" ]; then
		if [ ! -e "$tarball_file_path" ]; then
			msg
			msg "${BRED}Error: file '${YELLOW}${tarball_file_path}${YELLOW}' does not exist.${RST}"
			command_restore_help
			return 1
		fi

		if [ -d "$tarball_file_path" ]; then
			msg
			msg "${BRED}Error: path '${YELLOW}${tarball_file_path}${YELLOW}' is a directory.${RST}"
			command_restore_help
			return 1
		fi
	else
		if [ -t 0 ]; then
			msg
			msg "${BRED}Error: tarball file path is not specified and it looks like nothing is being piped via stdin either.${RST}"
			command_restore_help
			return 1
		fi
	fi

	# Notify user if tar available in PATH is not GNU tar.
	if ! grep -q 'tar (GNU tar)' <(tar --version 2>/dev/null | head -n 1); then
		msg
		msg "${BRED}Warning: tar binary that is available in PATH appears to be not a GNU tar. You may experience issues during installation, backup and restore operations.${RST}"
		msg
	fi

	local success
	msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Extracting distribution plug-in and rootfs from the tarball...${RST}"
	if [ -n "${tarball_file_path-}" ]; then
		if mkdir -p "${INSTALLED_ROOTFS_DIR}" && tar -x --auto-compress -f "$tarball_file_path" \
			--recursive-unlink --preserve-permissions \
			-C "${DISTRO_PLUGINS_DIR}/../" "$(basename "${DISTRO_PLUGINS_DIR}")/" \
			-C "${INSTALLED_ROOTFS_DIR}/../" "$(basename "${INSTALLED_ROOTFS_DIR}")/"; then
			success=true
		else
			success=false
		fi
	else
		if mkdir -p "${INSTALLED_ROOTFS_DIR}" && tar -x --recursive-unlink --preserve-permissions \
			-C "${DISTRO_PLUGINS_DIR}/../" "$(basename "${DISTRO_PLUGINS_DIR}")/" \
			-C "${INSTALLED_ROOTFS_DIR}/../" "$(basename "${INSTALLED_ROOTFS_DIR}")/"; then
			success=true
		else
			success=false
		fi
	fi

	if $success; then
		msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Finished.${RST}"
	else
		msg "${BLUE}[${RED}!${BLUE}] ${CYAN}Failure.${RST}"
		msg
		msg "${BRED}Failed to restore distribution from the given tarball.${RST}"
		msg
		msg "${BRED}Possibly that tarball was corrupted or not made by PRoot-Distro. Note that tarball piped to stdin must be decompressed.${RST}"
		msg
	fi
}

command_restore_help() {
	msg
	msg "${BYELLOW}Usage: ${BCYAN}${PROGRAM_NAME} ${GREEN}restore ${CYAN}[${GREEN}FILENAME.TAR${CYAN}]${RST}"
	msg
	msg "${CYAN}Restore distribution installation from a specified tarball. If${RST}"
	msg "${CYAN}file name is not specified, it will be assumed that tarball is${RST}"
	msg "${CYAN}being piped from stdin.${RST}"
	msg
	msg "${CYAN}Options:${RST}"
	msg
	msg "  ${GREEN}--help               ${CYAN}- Show this help information.${RST}"
	msg
	msg "${CYAN}Archive compression is determined automatically from the file${RST}"
	msg "${CYAN}extension. When archive content is piped it is expected that${RST}"
	msg "${CYAN}data is not compressed.${RST}"
	msg
	msg "${CYAN}Important note: there are no any sanity check being performed${RST}"
	msg "${CYAN}on the supplied tarballs. Be careful when using this command as${RST}"
	msg "${CYAN}data loss may happen when the wrong tarball was used.${RST}"
	msg
	show_version
	msg
}

#############################################################################
#
# FUNCTION TO CLEAR DOWNLOAD CACHE
#
# Delete all cached rootfs archives.
#
#############################################################################

command_clear_cache() {
	while (($# >= 1)); do
		case "$1" in
			-h|--help)
				command_clear_cache_help
				return 0
				;;
			-*)
				msg
				msg "${BRED}Error: got unknown option '${YELLOW}${1}${BRED}'.${RST}"
				command_clear_cache_help
				return 1
				;;
			*)
				msg
				msg "${BRED}Error: got excessive positional argument '${YELLOW}${1}${BRED}'.${RST}"
				command_clear_cache_help
				return 1
				;;
		esac
	done

	if ! ls -la "${DOWNLOAD_CACHE_DIR}"/* > /dev/null 2>&1; then
		msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Download cache is empty.${RST}"
	else
		local size_of_cache
		size_of_cache="$(du -d 0 -h -a ${DOWNLOAD_CACHE_DIR} | awk '{$2=$2};1' | cut -d " " -f 1)"

		msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Clearing cache files...${RST}"

		local filename
		while read -r filename; do
			msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Deleting ${CYAN}'${filename}'${RST}"
			rm -f "${filename}"
		done < <(find "${DOWNLOAD_CACHE_DIR}" -type f)

		msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Reclaimed ${size_of_cache} of disk space.${RST}"
	fi

	msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Finished.${RST}"
}

command_clear_cache_help() {
	msg
	msg "${BYELLOW}Usage: ${BCYAN}${PROGRAM_NAME} ${GREEN}clear-cache${RST}"
	msg
	msg "${CYAN}Command aliases: ${GREEN}clear${CYAN}, ${GREEN}cl${RST}"
	msg
	msg "${CYAN}Remove all cached rootfs archives to reclaim disk space.${RST}"
	msg
	show_version
	msg
}


#############################################################################
#
# FUNCTION TO COPY FILES FROM/TO DISTRIBUTION
#
# A wrapper for "cp" ("mv") coreutils command replacing distribution reference
# with a real path.
#
# Distribution reference format is: <dist-alias>:/absolute/path/to/file
#
#############################################################################

command_copy() {
	local source destination
	local src_path dest_path
	local src_distribution dest_distribution
	local verbose=false
	local mv_mode=false

	while (($# >= 1)); do
		case "$1" in
			-h|--help)
				command_copy_help
				return 0
				;;
			-v|--verbose)
				verbose=true
				;;
			-m|--move)
				mv_mode=true
				;;
			-*)
				msg
				msg "${BRED}Error: got unknown option '${YELLOW}${1}${BRED}'.${RST}"
				command_copy_help
				return 1
				;;
			*)
				if [ -z "${source-}" ]; then
					if [ -z "$1" ]; then
						msg
						msg "${BRED}Error: source file argument should not be empty.${RST}"
						command_copy_help
						return 1
					fi
					source="$1"
				elif [ -z "${destination-}" ]; then
					if [ -z "$1" ]; then
						msg
						msg "${BRED}Error: destination file argument should not be empty.${RST}"
						command_copy_help
						return 1
					fi
					destination="$1"
				else
					msg
					msg "${BRED}Error: got excessive positional argument '${YELLOW}${1}${BRED}'.${RST}"
					command_copy_help
					return 1
				fi
				;;
		esac
		shift 1
	done

	if [ -z "${source-}" ]; then
		msg
		msg "${BRED}Error: missing source file path argument.${RST}"
		command_copy_help
		return 1
	fi

	if [ -z "${destination-}" ]; then
		msg
		msg "${BRED}Error: missing destination file path argument.${RST}"
		command_copy_help
		return 1
	fi

	# Evaluate source path.
	src_distribution=$(grep -qP ':' <<< "${source}" && cut -d':' -f1 <<< "${source}" || true)
	src_path=$(cut -d':' -f2- <<< "${source}")
	if [ -n "${src_distribution}" ]; then
		if [ -d "${INSTALLED_ROOTFS_DIR}/${src_distribution}" ]; then
			src_path=$(realpath -m "${INSTALLED_ROOTFS_DIR}/${src_distribution}/${src_path}")
		else
			msg
			msg "${BRED}Error: distribution '${YELLOW}${src_distribution}${BRED}' is not installed.${RST}"
			msg
			return 1
		fi
	else
		src_path=$(realpath -m "${src_path}")
	fi
	if [ ! -e "${src_path}" ]; then
		msg
		msg "${BRED}Error: can't copy '${YELLOW}${source}${BRED}' because file does not exist.${RST}"
		msg
		return 1
	fi

	# Evaluate destination path.
	dest_distribution=$(grep -qP ':' <<< "${destination}" && cut -d':' -f1 <<< "${destination}" || true)
	dest_path=$(cut -d':' -f2- <<< "${destination}")
	if [ -n "${dest_distribution}" ]; then
		if [ -d "${INSTALLED_ROOTFS_DIR}/${dest_distribution}" ]; then
			dest_path=$(realpath -m "${INSTALLED_ROOTFS_DIR}/${dest_distribution}/${dest_path}")
		else
			msg
			msg "${BRED}Error: distribution '${YELLOW}${dest_distribution}${BRED}' is not installed.${RST}"
			msg
			return 1
		fi
	else
		dest_path=$(realpath -m "${dest_path}")
	fi
	#if [ -e "${dest_path}" ]; then
	#	msg
	#	msg "${BRED}Error: destination file '${YELLOW}${destination}${BRED}' already exist, refusing to overwrite.${RST}"
	#	msg
	#	return 1
	#fi

	msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Source: '${src_path}'${RST}"
	msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Destination: '${dest_path}'${RST}"

	if [ ! -e "$(dirname "${dest_path}")" ]; then
		msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Creating directory '$(dirname "${dest_path}")'...${RST}"
		if ! mkdir -p "$(dirname "${dest_path}")"; then
			msg "${BLUE}[${RED}!${BLUE}] ${CYAN}Failure.${RST}"
			msg
			msg "${BRED}Error: unable to create directory at '${YELLOW}$(dirname "${dest_path}")${BRED}'.${RST}"
			msg
			return 1
		fi
	fi

	if ${mv_mode}; then
		msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Moving files...${RST}"

		if ! mv "${src_path}" "${dest_path}"; then
			msg "${BLUE}[${RED}!${BLUE}] ${CYAN}Failure.${RST}"
			msg
			msg "${BRED}Error: unable to move file into '${YELLOW}${dest_path}${BRED}'.${RST}"
			msg
			return 1
		fi
	else
		msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Copying files, this may take a while...${RST}"
		local extra_cp_flags=""
		${verbose} && extra_cp_flags="-v"
		${verbose} && msg

		# Always use archive mode as argument allowed to be either a file or directory.
		if ! cp -a ${extra_cp_flags} "${src_path}" "${dest_path}"; then
			${verbose} && msg
			msg "${BLUE}[${RED}!${BLUE}] ${CYAN}Failure.${RST}"
			msg
			msg "${BRED}Error: unable to copy file into '${YELLOW}${dest_path}${BRED}'.${RST}"
			msg
			return 1
		fi

		${verbose} && msg
	fi

	msg "${BLUE}[${GREEN}*${BLUE}] ${CYAN}Finished.${RST}"
}

command_copy_help() {
	msg
	msg "${BYELLOW}Usage: ${BCYAN}${PROGRAM_NAME} ${GREEN}copy ${CYAN}[${GREEN}OPTIONS] ${CYAN}[${GREEN}DIST-ALIAS:${CYAN}]${GREEN}SRC ${CYAN}[${GREEN}DIST-ALIAS:${CYAN}]${GREEN}DEST${RST}"
	msg
	msg "${CYAN}Command aliases: ${GREEN}cp${RST}"
	msg
	msg "${CYAN}Copy files from/to distribution.${RST}"
	msg
	msg "${CYAN}Both source and destination arguments may be either as a local${RST}"
	msg "${CYAN}path or path of file inside distribution container.${RST}"
	msg
	msg "${CYAN}Options:${RST}"
	msg
	msg "  ${GREEN}--help               ${CYAN}- Show this help information.${RST}"
	msg
	msg "  ${GREEN}--move               ${CYAN}- Move instead of copying.${RST}"
	msg
	msg "  ${GREEN}--verbose            ${CYAN}- Show the log of copied files.${RST}"
	msg
	msg "${CYAN}Glob is not supported. Only one file or directory can be copied${RST}"
	msg "${CYAN}at a time.${RST}"
	msg
	msg "${CYAN}Example how to copy local file to distribution:${RST}"
	msg
	msg "  ${GREEN}${PROGRAM_NAME} copy ./file.txt ubuntu:/root/file.txt${RST}"
	msg
	show_version
	msg
}

#############################################################################
#
# FUNCTION TO PRINT UTILITY USAGE INFORMATION
#
# Prints a description of PRoot-Distro utility and list of the available
# commands.
#
#############################################################################

command_help() {
	msg
	msg "${BYELLOW}Usage: ${BCYAN}${PROGRAM_NAME}${CYAN} [${GREEN}COMMAND${CYAN}] [${GREEN}ARGUMENTS${CYAN}]${RST}"
	msg
	msg "${CYAN}PRoot-Distro is a Bash script wrapper for PRoot. It provides${RST}"
	msg "${CYAN}a set of functions with standardized command line interface${RST}"
	msg "${CYAN}to let user easily manage Linux PRoot containers. By default${RST}"
	msg "${CYAN}it supports a number of well known Linux distributions such${RST}"
	msg "${CYAN}Alpine Linux, Debian or openSUSE. However it is possible to${RST}"
	msg "${CYAN}add others with a help of plug-ins.${RST}"
	msg
	msg "${CYAN}List of the available commands:${RST}"
	msg
	msg "  ${GREEN}help         ${CYAN}- Show this help information.${RST}"
	msg
	msg "  ${GREEN}backup       ${CYAN}- Backup a specified distribution.${RST}"
	msg
	msg "  ${GREEN}install      ${CYAN}- Install a specified distribution.${RST}"
	msg
	msg "  ${GREEN}list         ${CYAN}- List supported distributions and their${RST}"
	msg "                 ${CYAN}installation status.${RST}"
	msg
	msg "  ${GREEN}login        ${CYAN}- Start login shell for the specified distribution.${RST}"
	msg
	msg "  ${GREEN}remove       ${CYAN}- Delete a specified distribution.${RST}"
	msg "                 ${RED}WARNING: this command destroys data!${RST}"
	msg
	msg "  ${GREEN}rename       ${CYAN}- Rename installed distribution.${RST}"
	msg
	msg "  ${GREEN}reset        ${CYAN}- Reinstall from scratch a specified distribution.${RST}"
	msg "                 ${RED}WARNING: this command destroys data!${RST}"
	msg
	msg "  ${GREEN}restore      ${CYAN}- Restore a specified distribution.${RST}"
	msg "                 ${RED}WARNING: this command destroys data!${RST}"
	msg
	msg "  ${GREEN}clear-cache  ${CYAN}- Clear cache of downloaded files. ${RST}"
	msg
	msg "  ${GREEN}copy         ${CYAN}- Copy files from/to distribution. ${RST}"
	msg
	msg "${CYAN}Each of commands has its own help information. To view it, just${RST}"
	msg "${CYAN}supply a '${GREEN}--help${CYAN}' argument to chosen command.${RST}"
	msg
	msg "${CYAN}Hint: type command '${GREEN}${PROGRAM_NAME} list${CYAN}' to get a list of the${RST}"
	msg "${CYAN}supported distributions. Pick a distro alias and run the next${RST}"
	msg "${CYAN}command to install it: ${GREEN}${PROGRAM_NAME} install <alias>${RST}"
	msg
	msg "${CYAN}Runtime data is stored at this location:${RST}"
	msg
	msg "${YELLOW}  ${RUNTIME_DIR}${RST}"
	msg
	msg "${CYAN}If you have issues with proot during installation or login, try${RST}"
	msg "${CYAN}to set '${GREEN}PROOT_NO_SECCOMP=1${CYAN}' environment variable.${RST}"
	msg
	show_version
	msg
}

#############################################################################
#
# FUNCTION TO PRINT VERSION STRING
#
# Prints version & author information. Used in functions for displaying
# usage info.
#
#############################################################################

show_version() {
	msg "${ICYAN}Proot-Distro v${PROGRAM_VERSION} by Termux (@sylirre).${RST}"
}

#############################################################################
#
# ENTRY POINT
#
# 1. Determine device properties such as CPU architecture.
# 2. Check all available distribution plug-ins.
# 3. Handle the requested commands or show help when '-h/--help/help' were
#    given. Further command line processing is offloaded to requested command.
#
#############################################################################

# This will be executed when signal HUP/INT/TERM is received.
trap 'echo -e "\\r${BLUE}[${RED}!${BLUE}] ${CYAN}Exiting immediately as requested.${RST}"; exit 1;' HUP INT TERM

# Determine a CPU architecture of device.
case "$(uname -m)" in
	# Note: armv8l means that device is running 32bit OS on 64bit CPU.
	armv7l|armv8l) DEVICE_CPU_ARCH="arm";;
	*) DEVICE_CPU_ARCH=$(uname -m);;
esac
DISTRO_ARCH=${DISTRO_ARCH:-}
if [ -z "$DISTRO_ARCH" ]; then DISTRO_ARCH="${DEVICE_CPU_ARCH}"; fi

# Verify architecture if possible - avoid running under linux32 or similar.
if [ -x "@TERMUX_PREFIX@/bin/dpkg" ]; then
	if [ "$DEVICE_CPU_ARCH" != "$("@TERMUX_PREFIX@"/bin/dpkg --print-architecture)" ]; then
		msg
		msg "${BRED}Error: the CPU architecture reported by system does not match the architecture of Termux packages. Do not attempt to hijack system properties by using 'linux32' or similar utilities.${RST}"
		msg
		exit 1
	fi
fi

# Check if architecture supports 32-bit instructions.
SUPPORT_32BIT=true
if grep -q "CPU op-mode" <(lscpu) 2>/dev/null && ! grep -qE 'CPU op-mode\(s\):.*32-bit' <(lscpu) 2>/dev/null; then
	SUPPORT_32BIT=false
fi

declare -A TARBALL_URL TARBALL_SHA256
declare -A SUPPORTED_DISTRIBUTIONS
declare -A SUPPORTED_DISTRIBUTIONS_COMMENTS
while read -r filename; do
	# shellcheck disable=SC1090
	distro_name=$(. "$filename"; echo "${DISTRO_NAME-}")
	# shellcheck disable=SC1090
	distro_comment=$(. "$filename"; echo "${DISTRO_COMMENT-}")
	# May have 2 name formats:
	# * alias.override.sh
	# * alias.sh
	# but we need to treat both as 'alias'.
	distro_alias=${filename%%.override.sh}
	distro_alias=${distro_alias%%.sh}
	distro_alias=$(basename "$distro_alias")

	# We getting distribution name from $DISTRO_NAME which
	# should be set in plug-in.
	if [ -z "$distro_name" ]; then
		msg
		msg "${BRED}Error: no DISTRO_NAME defined in '${YELLOW}${filename}${BRED}'.${RST}"
		msg
		exit 1
	fi

	SUPPORTED_DISTRIBUTIONS["$distro_alias"]="$distro_name"
	[ -n "$distro_comment" ] && SUPPORTED_DISTRIBUTIONS_COMMENTS["$distro_alias"]="$distro_comment"
done < <(find "$DISTRO_PLUGINS_DIR" -maxdepth 1 \( -type f -o -type l \) -iname "*.sh" 2>/dev/null)
unset distro_name distro_alias

if [ $# -ge 1 ]; then
	case "$1" in
		-h|--help|help|hel|he|h) shift 1; command_help;;
		backup|bak|bkp) shift 1; command_backup "$@";;
		install|i|in|ins|add) shift 1; command_install "$@";;
		list|li|ls) shift 1; command_list "$@";;
		login|sh) shift 1; command_login "$@";;
		remove|rm) shift 1; CMD_REMOVE_REQUESTED_RESET="false" command_remove "$@";;
		rename|mv) shift 1; command_rename "$@";;
		clear-cache|clear|cl) shift 1; command_clear_cache "$@";;
		copy|cp) shift 1; command_copy "$@";;

		# Not implementing aliases as they could be confusing.
		# We don't have many choices for these two commands: r, re, res, rst.
		reset) shift 1; command_reset "$@";;
		restore) shift 1; command_restore "$@";;

		*)
			msg
			msg "${BRED}Error: unknown command '${YELLOW}${1}${BRED}'.${RST}"
			msg
			msg "${CYAN}View supported commands by: ${GREEN}${PROGRAM_NAME} help${CYAN}${RST}"
			msg
			exit 1
			;;
	esac
else
	msg
	msg "${BRED}Error: no command provided.${RST}"
	command_help
fi

exit 0
